Disclaimer .... it not the switch its a cabling issue.
I have been using my original RCS 4 for 3 years now and it has been 100% solid. Its just up behind the house with about a 150' of RG214 "control" IFL between the house and the switch. I have a 20m, 17m, 30m 1/4 GP and a 20m 5/8 GP hooked up and working fine!
Bought a 2nd RCS 4 last summer , stuck it at the top of the hill with a run of close to 500' of LDF4. The center conductor is at least 10-12 gauge and it has a solid aluminium jacket....next to no loss at HF! I had been using this chunk of IFL for close to 20 years with a 14avq .... just moved it off the AVQ and onto the sw and presto I can ass 3 more antennas at the top of the hill or so I thought. Now at first all was well but in October when I made the 80m 1/4 gp suddenly there was an intermittent S9+++ noise and it was coming from my switch!!!! So I gave up brought it into the shack and used it inside for months working flawlessly! I made an assumption that perhaps with such a long run of cable there was too much of a voltage drop for the +12 VDC, -12 VDC and 12 VAC control signals.
First ruler of thumb....NEVER and I mean NEVER rely on an " assumption"!
OK so fast forward to this Summer.
Decided to install the " new " switch up behind the house ... about 150' control IFL the do 4 runs of LDF 4 up the hill. ( LDF 4 was discarded from work due to a little backhoe incident ). So it took days to run the cable and do the necessary splices. At first everything was 100% working until suddenly the S9 +++ noise was back. I was shall we say rather unpleasantly surprised. The thing that blew me away was I was on completely different chunk of cable between the house and control box....go figure.
So I had a head scratchier...dug into the drawings , read everything online and came upp with a game plan.
First ... lots of comments about shotty manufacturing. The design is simple , bullet proof actually! Brought the box in opened it up and found that the SO239's that are attached to the case are soldered directly to the PC board so doing a once over re soldering would be tricky with no access to the bottom of the PC board. The center pins of the S0239 soldering on 3 of the 5 connectors didn't appear to make it through to the back side of the PC board. So I used a focused propane torch and heated up the top side of the board while applying solder to the underside until I had a nice little bead. Tested the box on the bench overnight WSPRerin on 40m ...100%!
Installed the box today , turned on a BANG the noise was back .... disappointing but not surprised!
Plan C, D, E, F......
1) Lifted the Ground on the control box .... same noise!
2) Swapped 3 year old box with the new box and to my surprise the noise moved to the old box that performed flawlessly for the past 3 years!
So , it has nothing to do with the control boxes!!!!!!
3) The two control ( switch boxes ) are about 50' apart so I grabbed a chunk of 214 and ran it from the old control box to the new one and hooked it up with the old cable run and it worked 100% .
So I just for laugh's and giggles I connected the new cable to the old the original box and presto the fault moved!
NOW for the real kicker!!!!!!!!!!!
With the new "control " cable un-terminated I turned the power on fro the control box and BAM the noise is back.
So .... I have a fault with the control cable that is causing white noise across the HF spectrum. First thought was connectors! If not connectors that the cable is at fault!!!!!!!
I only have one spare PL259 ( note to self order more PL259s ) so I am debating on which one to lob off!!!! Its a nice day so I am heading outside!!!!!
....to be continued
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