Hi Gerald. Nice explanation. I note that many Hams insist on putting drain holes in lna and relay boxes! Spending SEVEN YEARS in the Panama Canal and also fixing com stuff in the Perlas Islands we always double boxed and used silicone rubber to fill up spaces, except for really big areas. Note that the connectors for some coax are very expensive and still require hand tools and special hardware...(The Price of Excellence, Eh?) Dave...W9DCO -----Original Message----- From: TexasRF &lt;TexasRF(a)aol.com&gt; To: ok1dfc &lt;ok1dfc(a)seznam.cz&gt;cz>; chejmw &lt;chejmw(a)buffalo.edu&gt;du>; moon-net &lt;moon-net(a)mailman.pe1itr.com&gt;om>; gamma7777 &lt;gamma7777(a)aol.com&gt; Sent: Thu, Dec 8, 2011 5:48 pm Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Zdenek and All, your mention of hollow center conductors and water condensation brought back some bad memories of this problem. I use LDF5-50A Heliax for long four way power dividers that also serve the purpose of phasing lines on my 48 X 10-el 2m array. Some of the power dividers are about 25ft long on each side for a total of about 50ft. When first installed in 1992, the lower Heliax connectors would fill with water droplets over a two to three week time period. At first I thought my sealing job was at fault but eventually it became apparent that the water was leaking around the screw in center pin from the hollow center conductor and flooding the connector. Tarnished threads were the give away. The solution turned out to be easy: the center pin threads were wrapped with a couple of layers of plumbers teflon tape before screwing them in. Just as in a plumbing application, the tape sealed the threads and to this day there have been no further water problems. So, every Heliax connector with threaded center pins now get this treatment. Newer connectors with the push on center pins will need a different solution. I have not tried but it makes some sense to inject silicone sealant into the center conductor when using the new style connectors. 73, Gerald K5GW In a message dated 12/8/2011 3:13:19 P.M. Central Standard Time, <mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz writes: You did not understood me well Jim, I say seriously that cable is nice! Many professional application is using that. I was only trying to introduce new version of our cable which has not empty central conductor which avoid condensation trough long time installation periods. Otherwise you have to take more care about checking connectors periodically etc. We still produce this kind of cable, reason is, that not so many is able pay higher price for CR cables and FHJ cables are very good usable for many systems. Reason why we developed CR is, that there is not corrugate surface of outer conductor and cable has very good SWR due to absence of periodical impedance exchanging. That is all. Also my sentence that best cable is cable which is used means that if anybody will buy offered cable it will be better as have the cable in stock or so. Nothing worse I did not say. Regards Zdenek - OK1DFC <http://www.ok1dfc.com/>www.ok1dfc.com QRV EME 432-1296-2320-3400 MHz WAC 432 - 1296 MHz QRO - 10m dish -----Original Message----- From: <mailto:moon-net-bounces@mailman.pe1itr.com>moon-net-bounces@mailman.pe1itr.com [mailto:moon-net-bounces@mailman.pe1itr.com]On Behalf Of James M. Walker Sent: Thursday, December 08, 2011 9:46 PM To: <mailto:moon-net@mailman.pe1itr.com>moon-net@mailman.pe1itr.com; Dave..W9DCO Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Dave, I think the phrase that is appropriate is Oh My!!!!!! I have the coil just sitting there, right next to the 1 Kw 2 meter amplifier, seems my first thought was the right one. I'm getting too old to argue specifications with folks. Might find a repeater owner that wants it, there is always the "scrap alternative. Tnx and BCNU Jim WB2FCN/WD2XSH-22 ----- Original Message ----- From: <mailto:gamma7777@aol.com>Dave..W9DCO To: <mailto:chejmw@buffalo.edu>chejmw@buffalo.edu ; <mailto:moon-net@mailman.pe1itr.com>moon-net@mailman.pe1itr.com Sent: Thursday, December 08, 2011 3:09 PM Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Jim. Hey, all of us have one speed.Slow... and the MB gang are mostly poor as Church Mice.... It takes a while for any of us to figure out connectors, losses, lengths... Tnx for trying to help the Gang.. Dave...W9DCO.... BTW..Great Cabinets...but shipping! -----Original Message----- From: James M. Walker <<mailto:chejmw@buffalo.edu>chejmw@buffalo.edu> To: OK1DFC <<mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz>; peter blair <<mailto:g3ltf@btinternet.com>g3ltf@btinternet.com>; melum <<mailto:melum@alaska.net>melum@alaska.net> Cc: moon-net <<mailto:moon-net@mailman.pe1itr.com>moon-net@mailman.pe1itr.com> Sent: Thu, Dec 8, 2011 12:41 pm Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Zdenek, sorry mate just got a real sweet Idea from Stan, W1LE Cape Cod FN41sr I will cut it into 2 foot lengths and sell it as scrap copper, no sense trying to sell it to anyone who might use it! Thanks Jim WB2FCN ----- Original Message ----- From: OK1DFC To: James M. Walker ; peter blair ; melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Sent: Thursday, December 08, 2011 12:54 PM Subject: RE: [Moon-net] Power handling - RG213 RG214 Nice cable Jim, we as a CommScope, previous Andrew producing this cable in Catawba N.C. Much better, comparing with FHJ cable is CR1070 http://www.ok1dfc.com/eme/10mprojekt/commcable/index.html :-), but as I say, best cable is cable which you have in your garage or better instaled between Antenna and PA :-) If anybody need more info about Andrew stuff, let me know. Zdenek - OK1DFC www.ok1dfc.com QRV EME 432-1296-2320-3400 MHz WAC 432 - 1296 MHz QRO - 10m dish -----Original Message----- From: moon-net-bounces(a)mailman.pe1itr.com [mailto:moon-net-bounces@mailman.pe1itr.com]On Behalf Of James M. Walker Sent: Thursday, December 08, 2011 6:22 PM To: peter blair; melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Subject: Re: [Moon-net] Power handling - RG213 RG214 How about some FHJ5-50A, got a 200 ft roll. http://eshop1.chem.buffalo.edu/Forsale.html Jim WB2FCN ----- Original Message ----- From: peter blair To: melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Sent: Thursday, December 08, 2011 11:37 AM Subject: Re: [Moon-net] Power handling - RG213 RG214 the center conductor, hot, slowly migrated (perhaps weeks/months) from centered position, laterally through the polyethylene to short circuit position on the shield, on the inside of the bend radius, Been there, done that! 300-400W at 1296 and about an 8" radius on standard polythene type cable will do it on CW EME use.- I now use PTFE dielectric cable for jumpers... or FSJ4 heliax. 73 G3LTF ----- Original Message ----- From: Patrick Barthelow To: wa4njp(a)bellsouth.net ; moon(a)moonbounce.info ; moon-net(a)nlsa.com ; melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Sent: Wednesday, December 07, 2011 6:34 PM Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Mike, and group: I don't know the specific answer to your question, but I have a first hand tale of RG-8/213/214 cable. to enlighten... An FM broadcast station in Monterey, in the 1000 watt category, had an engineer in the local radio club that told the tale, about RG-8 Class cable, in the FM band, at the TX output, and in a jumper panel. Two cables, solid polyethylene dielectric, inside the TX building perhaps 14" long were connected to closely spaced N- Panel jacks, with a rather tight bend radius. The n Jacks were about 8" apart on the same aluminum panel. I put my hand on the cables, that had been in 24/7 use on FM radio at 1000 watts. IRRC, the cable outer jacket was definintely warm, to very warm to the touch. Earlier cables suffered a catastrophic failure (short circuit), and were replaced by longer cables, allowing a long bending radius. Post mortems of the failed cables, showed that the center conductor, hot, slowly migrated (perhaps weeks/months) from centered position, laterally through the polyethylene to short circuit position on the shield, on the inside of the bend radius, and of course, tripped the FM station off the air. Kind of like the short jumpers between the two switches in the center stack of this switch board, only with RG-8 cable : http://www.ac2c.net/images/Misc/Antenna-Switches_l.jpg Best Regards, Pat Barthelow; Echoes of Apollo ---------- Date: Wed, 7 Dec 2011 09:54:19 -0800 From: wa4njp(a)bellsouth.net To: moon(a)moonbounce.info; moon-net(a)nlsa.com; melum(a)alaska.net CC: moon-net(a)mailman.pe1itr.com Subject: Re: [Moon-net] Power handling - RG213 RG214 Mike It is my opinion that, if it has been working good for you , don't change.....there are a lot of qualifiers in the creation of the mfg specs... most don't apply to the operation we use in....There is coax that has a bit less loss at UHF but $$$ and some unhandy to work with especially if in short length.. Ray --- On Wed, 12/7/11, Mike KL6M &lt;melum(a)alaska.net&gt; wrote: From: Mike KL6M &lt;melum(a)alaska.net&gt; Subject: [Moon-net] Power handling - RG213 RG214 To: moon(a)moonbounce.info, moon-net(a)nlsa.com Cc: moon-net(a)mailman.pe1itr.com Date: Wednesday, December 7, 2011, 12:42 PM QST - experts! I have been using short sections of RG213 and RG214 for years in relay boxes and from the heliax to the feed at power levels greater than 1000 watts. It was just brought to my attention that these coaxes are only "officially" rated at ~800 watts or less. Is this really a problem? 73 Mike, KL6M BP51dc http://www.qsl.net/kl6m _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html ---------- _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html ---------- _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at <http://www.nlsa.com/nets/moon-net-help.html>http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html

Content-Type: multipart/alternative; boundary="----=_NextPart_000_0037_01CCB632.609E7840" Content-Language: en-us Hello Moonatics, Let me add to that below. My LNA and PA along with H/V relay and power supply has been outside for over 5 years now. I run a fan every night at a very slow rate. Actually it is two fans in series, one for the power supply and another for the LNA/PA. They are in separate boxes at the base of the antenna. These fans huge "muffin" fans and they run full speed when the equipment is on. Just last week I took down the 2 meter array and am putting up a 6 meter array. I cleaned out the boxes gave them a coat of paint and inspected the equipment for damage. I can report that the boxes have some mold, there are some dead insects and dirt but the equipment is in good shape. The equipment has some minor rust on some parts but otherwise fully functional. After 5 years running all night at half voltage only one of the fans has a bearing that has noticeable drag. And, they were used fans when I put them in 5 years ago. The secret, keep the air moving so it won't condense. This is in Florida. So Ed, your situation might be different. BTW: I still have my winter coat; to wear when I go north. J See ya, Al, K2BLA From: moon-net-bounces(a)mailman.pe1itr.com [mailto:moon-net-bounces@mailman.pe1itr.com] On Behalf Of Edward R. Cole Sent: Thursday, December 08, 2011 8:12 PM To: Dave..W9DCO; TexasRF(a)aol.com; moon-net(a)mailman.pe1itr.com Subject: Re: [Moon-net] Power handling - RG213 RG214 Dave and I have been trading notes on how we do things. Part of Dave's latest response is probably inspired by those exchanges (off the reflector). I noted to him that many of us allow air exchange in/out of our tower-top equipment boxes because experience had shown weather-proof sealing is not fool-proof. The expansion/contractions with change in temperature acts (to cause a partial vacuum) to suck in moist air which then condenses into water and cannot escape due to the seals blocking water. Most of us in temperate or colder climates have swing of temperatures that can even cause internal frost buildup. So providing small drain holes maintains the interior in equilibrium with outside conditions. Some have added a heat source to keep internal temps above the dew point. Dave's experience in Florida (semi-tropical) and Canal Zone (tropical) is contrary with waterproofing working better. A cold day in FL is 60F and folks put on their winter coats below 50. Freeze line in FL is near the latitude of Orlando (slightly south of that in recent years). 60F is fine sunny summer day where I live. Average winter day is 15-20F and we don't think "cold" until it reaches zero-F. Up in Fairbanks you adjust my numbers by subtracting 25 or 30 degrees. ;-) What I am saying is no one solution fits all! Too, often experience is still the best teacher. Boy has this discussion digressed far off topic (Power handling - RG213 RG214). 73, Ed - KL7UW (lat. 60.675N) At 03:10 PM 12/8/2011, Dave..W9DCO wrote: Hi Gerald. Nice explanation. I note that many Hams insist on putting drain holes in lna and relay boxes! Spending SEVEN YEARS in the Panama Canal and also fixing com stuff in the Perlas Islands we always double boxed and used silicone rubber to fill up spaces, except for really big areas. Note that the connectors for some coax are very expensive and still require hand tools and special hardware...(The Price of Excellence, Eh?) Dave...W9DCO -----Original Message----- From: TexasRF <<mailto:TexasRF@aol.com>TexasRF@aol.com> To: ok1dfc <<mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz>; chejmw <<mailto:chejmw@buffalo.edu>chejmw@buffalo.edu>; moon-net <<mailto:moon-net@mailman.pe1itr.com>moon-net@mailman.pe1itr.com>; gamma7777 <<mailto:gamma7777@aol.com>gamma7777@aol.com> Sent: Thu, Dec 8, 2011 5:48 pm Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Zdenek and All, your mention of hollow center conductors and water condensation brought back some bad memories of this problem. I use LDF5-50A Heliax for long four way power dividers that also serve the purpose of phasing lines on my 48 X 10-el 2m array. Some of the power dividers are about 25ft long on each side for a total of about 50ft. When first installed in 1992, the lower Heliax connectors would fill with water droplets over a two to three week time period. At first I thought my sealing job was at fault but eventually it became apparent that the water was leaking around the screw in center pin from the hollow center conductor and flooding the connector. Tarnished threads were the give away. The solution turned out to be easy: the center pin threads were wrapped with a couple of layers of plumbers teflon tape before screwing them in. Just as in a plumbing application, the tape sealed the threads and to this day there have been no further water problems. So, every Heliax connector with threaded center pins now get this treatment. Newer connectors with the push on center pins will need a different solution. I have not tried but it makes some sense to inject silicone sealant into the center conductor when using the new style connectors. 73, Gerald K5GW In a message dated 12/8/2011 3:13:19 P.M. Central Standard Time, <mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz writes: You did not understood me well Jim, I say seriously that cable is nice! Many professional application is using that. I was only trying to introduce new version of our cable which has not empty central conductor which avoid condensation trough long time installation periods. Otherwise you have to take more care about checking connectors periodically etc. We still produce this kind of cable, reason is, that not so many is able pay higher price for CR cables and FHJ cables are very good usable for many systems. Reason why we developed CR is, that there is not corrugate surface of outer conductor and cable has very good SWR due to absence of periodical impedance exchanging. That is all. Also my sentence that best cable is cable which is used means that if anybody will buy offered cable it will be better as have the cable in stock or so. Nothing worse I did not say. Regards Zdenek - OK1DFC <http://www.ok1dfc.com/>www.ok1dfc.com QRV EME 432-1296-2320-3400 MHz WAC 432 - 1296 MHz QRO - 10m dish -----Original Message----- From: <mailto:moon-net-bounces@mailman.pe1itr.com>moon-net-bounces@mailman.pe1itr.com [ mailto:moon-net-bounces@mailman.pe1itr.com]On Behalf Of James M. Walker Sent: Thursday, December 08, 2011 9:46 PM To: <mailto:moon-net@mailman.pe1itr.com>moon-net@mailman.pe1itr.com; Dave..W9DCO Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Dave, I think the phrase that is appropriate is Oh My!!!!!! I have the coil just sitting there, right next to the 1 Kw 2 meter amplifier, seems my first thought was the right one. I'm getting too old to argue specifications with folks. Might find a repeater owner that wants it, there is always the "scrap alternative. Tnx and BCNU Jim WB2FCN/WD2XSH-22 ----- Original Message ----- From: <mailto:gamma7777@aol.com>Dave..W9DCO To: <mailto:chejmw@buffalo.edu>chejmw@buffalo.edu ; <mailto:moon-net@mailman.pe1itr.com>moon-net@mailman.pe1itr.com Sent: Thursday, December 08, 2011 3:09 PM Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Jim. Hey, all of us have one speed.Slow... and the MB gang are mostly poor as Church Mice.... It takes a while for any of us to figure out connectors, losses, lengths... Tnx for trying to help the Gang.. Dave...W9DCO.... BTW..Great Cabinets...but shipping! -----Original Message----- From: James M. Walker <<mailto:chejmw@buffalo.edu>chejmw@buffalo.edu> To: OK1DFC <<mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz>; peter blair <<mailto:g3ltf@btinternet.com>g3ltf@btinternet.com>; melum <<mailto:melum@alaska.net>melum@alaska.net> Cc: moon-net <<mailto:moon-net@mailman.pe1itr.com> moon-net(a)mailman.pe1itr.com&gt; Sent: Thu, Dec 8, 2011 12:41 pm Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Zdenek, sorry mate just got a real sweet Idea from Stan, W1LE Cape Cod FN41sr I will cut it into 2 foot lengths and sell it as scrap copper, no sense trying to sell it to anyone who might use it! Thanks Jim WB2FCN ----- Original Message ----- From: OK1DFC To: James M. Walker ; peter blair ; melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Sent: Thursday, December 08, 2011 12:54 PM Subject: RE: [Moon-net] Power handling - RG213 RG214 Nice cable Jim, we as a CommScope, previous Andrew producing this cable in Catawba N.C. Much better, comparing with FHJ cable is CR1070 http://www.ok1dfc.com/eme/10mprojekt/commcable/index.html :-), but as I say, best cable is cable which you have in your garage or better instaled between Antenna and PA :-) If anybody need more info about Andrew stuff, let me know. Zdenek - OK1DFC www.ok1dfc.com QRV EME 432-1296-2320-3400 MHz WAC 432 - 1296 MHz QRO - 10m dish -----Original Message----- From: moon-net-bounces(a)mailman.pe1itr.com [ mailto:moon-net-bounces@mailman.pe1itr.com]On Behalf Of James M. Walker Sent: Thursday, December 08, 2011 6:22 PM To: peter blair; melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Subject: Re: [Moon-net] Power handling - RG213 RG214 How about some FHJ5-50A, got a 200 ft roll. http://eshop1.chem.buffalo.edu/Forsale.html Jim WB2FCN ----- Original Message ----- From: peter blair To: melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Sent: Thursday, December 08, 2011 11:37 AM Subject: Re: [Moon-net] Power handling - RG213 RG214 the center conductor, hot, slowly migrated (perhaps weeks/months) from centered position, laterally through the polyethylene to short circuit position on the shield, on the inside of the bend radius, Been there, done that! 300-400W at 1296 and about an 8" radius on standard polythene type cable will do it on CW EME use.- I now use PTFE dielectric cable for jumpers... or FSJ4 heliax. 73 G3LTF ----- Original Message ----- From: Patrick Barthelow To: wa4njp(a)bellsouth.net ; moon(a)moonbounce.info ; moon-net(a)nlsa.com ; melum(a)alaska.net Cc: moon-net(a)mailman.pe1itr.com Sent: Wednesday, December 07, 2011 6:34 PM Subject: Re: [Moon-net] Power handling - RG213 RG214 Hi Mike, and group: I don't know the specific answer to your question, but I have a first hand tale of RG-8/213/214 cable. to enlighten... An FM broadcast station in Monterey, in the 1000 watt category, had an engineer in the local radio club that told the tale, about RG-8 Class cable, in the FM band, at the TX output, and in a jumper panel. Two cables, solid polyethylene dielectric, inside the TX building perhaps 14" long were connected to closely spaced N- Panel jacks, with a rather tight bend radius. The n Jacks were about 8" apart on the same aluminum panel. I put my hand on the cables, that had been in 24/7 use on FM radio at 1000 watts. IRRC, the cable outer jacket was definintely warm, to very warm to the touch. Earlier cables suffered a catastrophic failure (short circuit), and were replaced by longer cables, allowing a long bending radius. Post mortems of the failed cables, showed that the center conductor, hot, slowly migrated (perhaps weeks/months) from centered position, laterally through the polyethylene to short circuit position on the shield, on the inside of the bend radius, and of course, tripped the FM station off the air. Kind of like the short jumpers between the two switches in the center stack of this switch board, only with RG-8 cable : http://www.ac2c.net/images/Misc/Antenna-Switches_l.jpg Best Regards, Pat Barthelow; Echoes of Apollo ---------- Date: Wed, 7 Dec 2011 09:54:19 -0800 From: wa4njp(a)bellsouth.net To: moon(a)moonbounce.info; moon-net(a)nlsa.com; melum(a)alaska.net CC: moon-net(a)mailman.pe1itr.com Subject: Re: [Moon-net] Power handling - RG213 RG214 Mike It is my opinion that, if it has been working good for you , don't change.....there are a lot of qualifiers in the creation of the mfg specs... most don't apply to the operation we use in....There is coax that has a bit less loss at UHF but $$$ and some unhandy to work with especially if in short length.. Ray --- On Wed, 12/7/11, Mike KL6M &lt;melum(a)alaska.net&gt; wrote: From: Mike KL6M &lt;melum(a)alaska.net&gt; Subject: [Moon-net] Power handling - RG213 RG214 To: moon(a)moonbounce.info, moon-net(a)nlsa.com Cc: moon-net(a)mailman.pe1itr.com Date: Wednesday, December 7, 2011, 12:42 PM QST - experts! I have been using short sections of RG213 and RG214 for years in relay boxes and from the heliax to the feed at power levels greater than 1000 watts. It was just brought to my attention that these coaxes are only "officially" rated at ~800 watts or less. Is this really a problem? 73 Mike, KL6M BP51dc http://www.qsl.net/kl6m _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html ---------- _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html ---------- _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at <http://www.nlsa.com/nets/moon-net-help.html>http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at <http://www.nlsa.com/nets/moon-net-help.html>http://www.nlsa.com/nets/moon-net-help.html 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz <http://www.kl7uw.com/>www.kl7uw.com EME: 50-1.1kw?, 144-1.4kw, 432-QRT, 1296-?, 3400-? DUBUS Magazine USA Rep <mailto:dubususa@gmail.com>dubususa@gmail.com ====================================== _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html

Hello All, FHJ cable is susceptible to Water absorption inside the foam. If water

LDF heliax is much better as it has closed cell foam which does not allow

I know we are all trying to do the best for the lowest possible cost. Best 73 Barry VE4MA ----- Original Message ----- From: "Edward R. Cole" &lt;kl7uw(a)acsalaska.net&gt; Date: Friday, December 9, 2011 10:19 am Subject: Re: [Moon-net] Power handling - RG213 RG214 To: Al Helfrick &lt;tubadoc(a)cfl.rr.com&gt;om>, moon-net(a)mailman.pe1itr.com > Al, > Novel Idea. But knowing how air quality is controlled in > tropical homes (air movement), it makes sense. Mold might > be controlled by use of air filters?? In cold country > supplemental heat is probably a good solution. My sspa for > 432 and 1296 (located on the back of the dish in Hoffman boxes) > will have fans so that is a possibility (plenty of heat when > operating, of course). > My equipment has changed over the years but the basic tower box > has been up since 1998-99 and I do see some rust showing on a > couple screw terminals of the barrier terminal strips I > use. No mold, but some small spider webs (no poisonous > spiders up here). Wasps seem uninterested and prefer under > my house eves (closer to ground). No squirrels or > birds. No black bears or moose, either! ;-) > Although, I had a moose run into the array this fall when I had > it cranked down for maint (antler envy?). > I'm also fortunate that there seems to be no wind-driven snow > getting in. My 600m loading coil enclosure at ground level > has some air openings and snow filled half the interior last year. > You probably don't worry about that. > 73, Ed - KL7UW > At 01:21 AM 12/9/2011, Al Helfrick wrote: > >Content-Type: multipart/alternative; > > boundary="---- > =_NextPart_000_0037_01CCB632.609E7840">Content-Language: en-us > > > >Hello Moonatics, > > > >Let me add to that below. > > > >My LNA and PA along with H/V relay and power supply has been > outside for over 5 years now. I run a fan every night at a very > slow rate. > >Actually it is two fans in series, one for the power supply and > another for the LNA/PA. They are in separate boxes at the base > of the antenna. These fans huge "muffin" fans and they run full > speed when the equipment is on. > > > >Just last week I took down the 2 meter array and am putting up > a 6 meter array. I cleaned out the boxes gave them a coat of > paint and inspected the equipment for damage. > > > >I can report that the boxes have some mold, there are some dead > insects and dirt but the equipment is in good shape. The > equipment has some minor rust on some parts but otherwise fully > functional. After 5 years running all night at half voltage only > one of the fans has a bearing that has noticeable drag. And, > they were used fans when I put them in 5 years ago. > > > >The secret, keep the air moving so it won't condense. This is > in Florida. So Ed, your situation might be different. > > > >BTW: I still have my winter coat; to wear when I go > north. J > > > >See ya, > > > >Al, K2BLA > > > >From: moon-net-bounces(a)mailman.pe1itr.com [mailto:moon-net- > bounces(a)mailman.pe1itr.com] On Behalf Of Edward R. Cole > >Sent: Thursday, December 08, 2011 8:12 PM > >To: Dave..W9DCO; TexasRF(a)aol.com; moon-net(a)mailman.pe1itr.com > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > > > >Dave and I have been trading notes on how we do things. > Part of Dave's latest response is probably inspired by those > exchanges (off the reflector). > > > >I noted to him that many of us allow air exchange in/out of our > tower-top equipment boxes because experience had shown weather- > proof sealing is not fool-proof. The > expansion/contractions with change in temperature acts (to cause > a partial vacuum) to suck in moist air which then condenses into > water and cannot escape due to the seals blocking water. > Most of us in temperate or colder climates have swing of > temperatures that can even cause internal frost buildup. > So providing small drain holes maintains the interior in > equilibrium with outside conditions. Some have added a > heat source to keep internal temps above the dew point. > > > >Dave's experience in Florida (semi-tropical) and Canal Zone > (tropical) is contrary with waterproofing working better. > A cold day in FL is 60F and folks put on their winter coats > below 50. Freeze line in FL is near the latitude of > Orlando (slightly south of that in recent years). 60F is > fine sunny summer day where I live. Average winter day is > 15-20F and we don't think "cold" until it reaches zero-F. > Up in Fairbanks you adjust my numbers by subtracting 25 or 30 > degrees. ;-) > > > >What I am saying is no one solution fits all! Too, often > experience is still the best teacher. > > > >Boy has this discussion digressed far off topic (Power handling > - RG213 RG214). > > > >73, Ed - KL7UW (lat. 60.675N) > > > >At 03:10 PM 12/8/2011, Dave..W9DCO wrote: > > > >Hi Gerald. > > > >Nice explanation. > >I note that many Hams insist on putting > >drain holes in lna and relay boxes! > >Spending SEVEN YEARS in the > >Panama Canal and also fixing com stuff > >in the Perlas Islands we always double > >boxed and used silicone rubber to > >fill up spaces, except for really big areas. > > > >Note that the connectors for some coax > >are very expensive and still require hand > >tools and special hardware...(The Price > >of Excellence, Eh?) > > > >Dave...W9DCO > > > > > >-----Original Message----- > >From: TexasRF <<mailto:TexasRF@aol.com>TexasRF@aol.com> > >To: ok1dfc <<mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz>; > chejmw <<mailto:chejmw@buffalo.edu>chejmw@buffalo.edu>; > moon-net <<mailto:moon-net@mailman.pe1itr.com>moon- > net(a)mailman.pe1itr.com&gt;gt;; gamma7777 > <<mailto:gamma7777@aol.com>gamma7777@aol.com>>Sent: Thu, > Dec 8, 2011 5:48 pm > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > > > >Hi Zdenek and All, your mention of hollow center conductors and > water condensation brought back some bad memories of this problem. > > > >I use LDF5-50A Heliax for long four way power dividers that > also serve the purpose of phasing lines on my 48 X 10-el 2m > array. Some of the power dividers are about 25ft long on > each side for a total of about 50ft. > > > >When first installed in 1992, the lower Heliax connectors would > fill with water droplets over a two to three week time period. > At first I thought my sealing job was at fault but eventually it > became apparent that the water was leaking around the screw in > center pin from the hollow center conductor and flooding the > connector. Tarnished threads were the give away. > > > >The solution turned out to be easy: the center pin threads were > wrapped with a couple of layers of plumbers teflon tape before > screwing them in. Just as in a plumbing application, the tape > sealed the threads and to this day there have been no further > water problems. > > > >So, every Heliax connector with threaded center pins now get > this treatment. Newer connectors with the push on center pins > will need a different solution. I have not tried but it makes > some sense to inject silicone sealant into the center conductor > when using the new style connectors. > > > >73, > >Gerald K5GW > > > > > > > > > >In a message dated 12/8/2011 3:13:19 P.M. Central Standard > Time, <mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz writes: > >You did not understood me well Jim, I say seriously that cable > is nice! Many professional application is using that. I was only > trying to introduce new version of our cable which has not empty > central conductor which avoid condensation trough long time > installation periods. Otherwise you have to take more care about > checking connectors periodically etc. We still produce this kind > of cable, reason is, that not so many is able pay higher price > for CR cables and FHJ cables are very good usable for many > systems. Reason why we developed CR is, that there is not > corrugate surface of outer conductor and cable has very good SWR > due to absence of periodical impedance exchanging. That is all. > >Also my sentence that best cable is cable which is used means > that if anybody will buy offered cable it will be better as have > the cable in stock or so. Nothing worse I did not say. > >Regards > > > >Zdenek - OK1DFC > ><http://www.ok1dfc.com/>www.ok1dfc.com > >QRV EME 432-1296-2320-3400 MHz > >WAC 432 - 1296 MHz > >QRO - 10m dish > >-----Original Message----- > >From: <mailto:moon-net-bounces@mailman.pe1itr.com>moon-net- > bounces(a)mailman.pe1itr.com [ mailto:moon-net- > bounces(a)mailman.pe1itr.com]On Behalf Of James M. Walker > >Sent: Thursday, December 08, 2011 9:46 PM > >To: <mailto:moon-net@mailman.pe1itr.com>moon- > net(a)mailman.pe1itr.com; Dave..W9DCO > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > >Hi Dave, > >I think the phrase that is appropriate is Oh My!!!!!! > >I have the coil just sitting there, right next to the > >1 Kw 2 meter amplifier, seems my first thought > >was the right one. I'm getting too old to argue specifications > >with folks. Might find a repeater owner that wants it, there > >is always the "scrap alternative. > >Tnx and BCNU > >Jim > >WB2FCN/WD2XSH-22 > > > > > >----- Original Message ----- > >From: <mailto:gamma7777@aol.com>Dave..W9DCO > >To: <mailto:chejmw@buffalo.edu>chejmw@buffalo.edu ; > <mailto:moon-net@mailman.pe1itr.com>moon-net@mailman.pe1itr.com > >Sent: Thursday, December 08, 2011 3:09 PM > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > >Hi Jim. > > > >Hey, all of us have one speed.Slow... > >and the MB gang are mostly poor as > >Church Mice.... > > > >It takes a while for any of us to figure > >out connectors, losses, lengths... > > > >Tnx for trying to help the Gang.. > > > >Dave...W9DCO.... > >BTW..Great Cabinets...but shipping! > > > >-----Original Message----- > >From: James M. Walker > <<mailto:chejmw@buffalo.edu>chejmw@buffalo.edu>>To: OK1DFC > <<mailto:ok1dfc@seznam.cz>ok1dfc@seznam.cz>; peter blair > <<mailto:g3ltf@btinternet.com>g3ltf@btinternet.com>; melum > <<mailto:melum@alaska.net>melum@alaska.net>>Cc: moon-net > <<mailto:moon-net@mailman.pe1itr.com> moon- > net(a)mailman.pe1itr.com&gt;&gt;Sentt;Sent: Thu, Dec 8, 2011 12:41 pm > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > >Hi Zdenek, > >sorry mate just got a real sweet Idea from Stan, > W1LE Cape Cod FN41sr > >I will cut it into 2 foot lengths and sell it as scrap copper, > no sense trying to > >sell it to anyone who might use it! > > > >Thanks > >Jim > >WB2FCN > > > >----- Original Message ----- > >From: OK1DFC > >To: James M. Walker ; peter blair ; melum(a)alaska.net > >Cc: moon-net(a)mailman.pe1itr.com > >Sent: Thursday, December 08, 2011 12:54 PM > >Subject: RE: [Moon-net] Power handling - RG213 RG214 > >Nice cable Jim, we as a CommScope, previous Andrew producing > this cable in Catawba N.C. Much better, comparing with FHJ cable > is CR1070 > http://www.ok1dfc.com/eme/10mprojekt/commcable/index.html :-), > but as I say, best cable is cable which you have in your garage > or better instaled between Antenna and PA :-) If anybody need > more info about Andrew stuff, let me know. > > > >Zdenek - OK1DFC > >www.ok1dfc.com > >QRV EME 432-1296-2320-3400 MHz > >WAC 432 - 1296 MHz > >QRO - 10m dish > >-----Original Message----- > >From: moon-net-bounces(a)mailman.pe1itr.com [ mailto:moon-net- > bounces(a)mailman.pe1itr.com]On Behalf Of James M. Walker > >Sent: Thursday, December 08, 2011 6:22 PM > >To: peter blair; melum(a)alaska.net > >Cc: moon-net(a)mailman.pe1itr.com > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > >How about some FHJ5-50A, got a 200 ft roll. > http://eshop1.chem.buffalo.edu/Forsale.html>Jim > >WB2FCN > > > >----- Original Message ----- > >From: peter blair > >To: melum(a)alaska.net > >Cc: moon-net(a)mailman.pe1itr.com > >Sent: Thursday, December 08, 2011 11:37 AM > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > > the center conductor, hot, slowly migrated (perhaps > weeks/months) from centered position, laterally through the > polyethylene to short circuit position on the shield, on > the inside of the bend radius, > > > >Been there, done that! 300-400W at 1296 and about an 8" > radius on standard polythene type cable will do it on CW EME > use.- I now use PTFE dielectric cable for jumpers... or FSJ4 heliax. > >73 G3LTF > >----- Original Message ----- > >From: Patrick Barthelow > >To: wa4njp(a)bellsouth.net ; moon(a)moonbounce.info ; moon- > net(a)nlsa.com ; melum(a)alaska.net > >Cc: moon-net(a)mailman.pe1itr.com > >Sent: Wednesday, December 07, 2011 6:34 PM > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > >Hi Mike, and group: > >I don't know the specific answer to your question, but I have a > first hand tale of RG-8/213/214 cable. to enlighten... > >An FM broadcast station in Monterey, in the 1000 watt category, > had an engineer in the local radio club that told the tale, about > >RG-8 Class cable, in the FM band, at the TX output, and in a > jumper panel. Two cables, solid polyethylene > dielectric, inside the TX building perhaps 14" long > were connected to closely spaced N- Panel jacks, with a rather > tight bend radius. The n Jacks were about 8" apart on the > same aluminum panel. I put my hand on the cables, that had > been in 24/7 use on FM radio at 1000 watts. IRRC, the > cable outer jacket was definintely warm, to very warm to > the touch. Earlier cables suffered a catastrophic > failure (short circuit), and were replaced by longer > cables, allowing a long bending radius. Post mortems > of the failed cables, showed that the center conductor, hot, > slowly migrated (perhaps weeks/months) from centered position, > laterally through the polyethylene to short circuit > position on the shield, on the inside of the bend radius, and of > course, tripped the FM station off the air. > >Kind of like the short jumpers between the two switches in the > center stack of this switch board, only with RG-8 cable : > >http://www.ac2c.net/images/Misc/Antenna-Switches_l.jpg > > > >Best Regards, > >Pat Barthelow; Echoes of Apollo > > > > > > > > > >---------- > >Date: Wed, 7 Dec 2011 09:54:19 -0800 > >From: wa4njp(a)bellsouth.net > >To: moon(a)moonbounce.info; moon-net(a)nlsa.com; melum(a)alaska.net > >CC: moon-net(a)mailman.pe1itr.com > >Subject: Re: [Moon-net] Power handling - RG213 RG214 > >Mike > > It is my opinion that, if it has been working good for > you , don't change.....there are a lot of qualifiers in the > creation of the mfg specs... most don't apply to the > operation we use in....There is coax that has a bit less loss at > UHF but $$$ and some unhandy to work with especially if in > short length.. > >Ray > >--- On Wed, 12/7/11, Mike KL6M &lt;melum(a)alaska.net&gt; wrote: > >From: Mike KL6M &lt;melum(a)alaska.net&gt; > >Subject: [Moon-net] Power handling - RG213 RG214 > >To: moon(a)moonbounce.info, moon-net(a)nlsa.com > >Cc: moon-net(a)mailman.pe1itr.com > >Date: Wednesday, December 7, 2011, 12:42 PM > >QST - experts! > >I have been using short sections of RG213 and RG214 for years > in relay > >boxes and from the heliax to the feed at power levels greater > than 1000 > >watts. > >It was just brought to my attention that these coaxes are only > >"officially" rated at ~800 watts or less. > >Is this really a problem? > >73 > >Mike, KL6M > BP51dc http://www.qsl.net/kl6m > > > > > >_______________________________________________ > >Moon-Net posting and subscription instructions are at > http://www.nlsa.com/nets/moon-net-help.html > > > >_______________________________________________ Moon-Net > posting and subscription instructions are at > http://www.nlsa.com/nets/moon-net-help.html > > > >---------- > >_______________________________________________ > >Moon-Net posting and subscription instructions are at > http://www.nlsa.com/nets/moon-net-help.html > > > >---------- > >_______________________________________________ > >Moon-Net posting and subscription instructions are at > http://www.nlsa.com/nets/moon-net-help.html > > > >_______________________________________________ > >Moon-Net posting and subscription instructions are at > http://www.nlsa.com/nets/moon-net-help.html > > > > > >_______________________________________________ > >Moon-Net posting and subscription instructions are at > <http://www.nlsa.com/nets/moon-net- > help.html>http://www.nlsa.com/nets/moon-net-help.html > >_______________________________________________ > >Moon-Net posting and subscription instructions are at > <http://www.nlsa.com/nets/moon-net- > help.html>http://www.nlsa.com/nets/moon-net-help.html > > > > > >73, Ed - KL7UW, WD2XSH/45 > >====================================== > >BP40IQ 500 KHz - 10-GHz > <http://www.kl7uw.com/>www.kl7uw.com>EME: 50-1.1kw?, 144- > 1.4kw, 432-QRT, 1296-?, 3400-? > >DUBUS Magazine USA Rep >

_______________________________________________ Moon-Net posting and subscription instructions are at

Kevin, Aquarium pumps work, but in humid climates it might not cut it. Here in the wet west coast of Canada it would be pushing all that humid air into the hardline. You would have to have to make a desiccant drier adapted to the small line. _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html

Years ago, while visiting a TV transmitter site, the engineer told me that they pressurized their coax with nitrogen. They would refill bottles at the local chemical company. It was cheap, easy to maintain and eliminated any chance at oxydation inside the coax. Paul, K7CW ------------------------------------------------------------------------ *From:* Mike &lt;ve7hmw(a)shaw.ca&gt; *To:* Kevin Hobbs &lt;ve3kh(a)cogeco.ca&gt; *Cc:* &quot;moon-net(a)mailman.pe1itr.com&quot; &lt;moon-net(a)mailman.pe1itr.com&gt; *Sent:* Friday, December 9, 2011 4:40 PM *Subject:* Re: [Moon-net] FHJ Heliax Cable Kevin, Aquarium pumps work, but in humid climates it might not cut it. Here in the wet west coast of Canada it would be pushing all that humid air into the hardline. You would have to have to make a desiccant drier adapted to the small line. _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html

It was in the 80s that I visited this station. I remember the coax being something like 5 or 6 inches in diameter. I got to look at a piece of it on the bench. PTFE disks kept the center conductor in position. The coax run up the tower was on the order of 400 metres long. There is a photo of me on the top platform of the tower on my web page. Paul K7CW From: GW8KBO &lt;gw8kbo(a)myleucarum.co.uk&gt; To: moon-net(a)mailman.pe1itr.com Sent: Tuesday, February 7, 2012 1:19 PM Subject: Re: [Moon-net] FHJ Heliax Cable In the mid 70s, I worked for EMI Antennas in Hayes, Middlesex, UK - all our air spaced antenna co-ax feeders were pressurised with dry nitrogen (up to 6.125 inch diam co-ax, often hundreds of feet long). Rarely any problems, as long as the connectors were made off correctly. If my memory serves me right, the highest quality cables were German - Kabelmetal I think. Steve GW8KBO On 10/12/2011 01:56, Paul Kiesel wrote: _______________________________________________ Moon-Net posting and subscription instructions are at <http://www.nlsa.com/nets/moon-net-help.html>http://www.nlsa.com/nets/moon-net-help.html _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html

On 12/10/2011 12:40 AM, Mike wrote: Here in the wet west coast of Canada it would be pushing > all that humid air into the hardline. You would have to have to make a desiccant drier adapted to the small line. I've used that system for some 30 years. A small aquarium pump pumps air into a quart jar filled with silica gel. A kid's "punch ball" balloon is attached to the jar lid to keep gentle pressure, and the balloon is surrounded by a piece of cardboard tp make a big tube with a micro switch inside so that the pump turns off when the balloon is properly inflated. A piece of half inch copper tubing and two small pieces of small "hobby" tubing are soldered into the jar lid for the balloon and pieces of small aquarium or similar tubing. This has been described in magazines several times over the years, tho haven't seen it for a long time. Open the jar and dry the silica gel in the oven once or twice per year. Biggest problem is the modern balloons - they don't last nearly as long as the old ones did. If the balloon does burst and you aren't around to change it, changing air pressure will cause the coax air to "breathe" thru the silica gel. So not pressurized for a while, but dry air still moving into it. Bottled air, nitrogen, other things also work. The above system works well and is cheap and interesting to make. Shelby, W8WN -- "Try not to have a good time..... This is supposed to be educational." Charles Schultz _______________________________________________ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html