Per the RCS-10 manual, you can put a shorted PL-259 in the Antenna 1
jack, and when you power down the control box, the line to the shack is
grounded. Since I only have 6 antennas, this is ideal, but I'm sure
others will grumble about the loss of one position. I put my dummy load
out there under a plastic bucket.
Aside from saving a little money on coax, it seems like a bad idea to
have your antenna switch at the top of the tower. I far prefer having
it at the bottom.
I have only had the RCS-10 for a few months, so we'll see how it goes in
the longer term, but so far every receiving problem has traced back to
the Stackmatch.
73, Pete N4ZR
The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at
reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000
On 8/9/2010 7:57 AM, Jim Thomson wrote:
> Date: Sun, 08 Aug 2010 10:44:45 -0400
> From: "Joe Subich, W4TV"<lists@subich.com>
> Subject: Re: [Amps] Automotive Relays
>
>
> > Currently using an RCS-10, which can have up to 7 relays in the
> > RF path. Will be interesting to see how it holds up.
>
> Since the relays are arranged in a "tree" (one feeding two, each
> of which feeds two more) there are always three relays in line to
> each antenna. See: http://ameritron.com/man/pdf/RCS-10.pdf
>
> 73,
>
> ... Joe, W4TV
>
> ## per the manual, there is exactly 3 x relays, nose to tail, in the
> circuit for any given ant.
> That means BOTH the RX + TX on some ports, is passing through NC
> contacts....that's a no-no..esp
> with mech relay's in an outdoor environment. Strike-1
>
> ## the RCS-10 will handle 8 [eight] ants. They used a total of 7 relays do
> accomplish this.
>
> ## NONE of the 8 ants have their center conductor's grnded, when not in use !
> More fubar. Strike-2
>
> ## A better technique would be to use 8 DPDT relays. Parallel all the
> contact's. Now you have some redundancy.
> Each ant port goes to the COM of it's own, dedicated relay. NC contact goes
> to grnd buss. NO contact goes to
> hot kw TX/RX main input buss.
>
> ## Ok, now with the above config, ALL DE-energized relay/ant port's have
> their center conductor's grnded...and right
> at the top of the tower. NO ant port ever gets connected to the input via
> NC contact's ! For added measure, you could
> add one extra SPDT-NC relay, and wire it between grnd + INPUT connector.
> Then during any thunderstorm activity, and
> all 9 relay's DE-energized, not only are all 8 ants grnded at top of
> tower, but the input is also grnded..at top of tower. A gas
> discharge tube on the input side of the box should also be used.
>
> ## the above box is how my Array solutions 20 kw rat pack came wired. They
> used DPDT-20A relays, with 20A contacts,
> and all contacts in parallel. 10 kv between any contacts, or contacts to
> armature/grnd. The 7-16 Din connector's I asked for,
> have a 4.5 mm gap between OD of the 7mm female inner tube and the 16mm ID
> of the outer tube. [16-7= 9mm. 9/2=4.5mm]
> 4.5mm = aprx 6300 v break down. You can get em in up to 12 positions.
> This box I have has no pc board traces at all. They
> used 3/4" wide Cu strap for both the NC grnd buss, and also the NO hot
> buss... and 5/16" spacing between em. This results
> in a 50 ohm strip line. Flat swr from 160-6m. Mine came in a die-cast al
> box.
>
> ## I added up what 7 connector's + 6 relays would cost, box, etc, and
> decided this was one item I was not going to hb for a change.
> There is no reason why you couldn't hb one of these things. I have also seen
> them using P+B DPDT power relays, with 30A contacts,
> again, with all contacts in parallel. To eliminate/minimize any contact
> issues, I re- silver plated all the contacts with the cool-amp goop.
> I then apply a thin coat of ..'conducto-lube' to all contacts. That stuff
> is just pure silver powder, suspended in grease.
> http://www.cool-amp.com/ I also had all the cu strap inside the box
> silver plated.
>
> I use 2 resistor's in parallel, to add heat inside the box. [ gold/metal
> finned dale type], again for redundancy, and also installed a bag
> of desiccant [silica gel]. The resistor/silica gel idea is also used on my
> nema box's, used for other stuff. This is as good as I could
> get it to my liking. Another method is to use SPDT vac relays..instead of
> DPDT mech relays... like Gigavac GH-1 G-2... or
> Jennings's RJ-1A / RJ-2B / C. ..or kilovac eq. I use vac relay's for
> all the BIP/BOP box's I design for friends. Then they are
> 110% bullet proof. There is no reason a SPDT relay [with all contacts in
> parallel] would not work for a simple BIP/BOP box.
> We gave up on the top/bottom/BIP/BOP circuit..and just use the BIP/BOP
> config. The BIP/BOP box's I cooked up use a
> simple LC config,with just a mess of NPO caps to grnd on the input... and a
> series CU tubing coil to output. The LC box is used
> for any 2 stacked yagi set up.[25 ohms output]... and also the 3 x yagi
> setup [16.67 ohms output]. This is for monoband ant's only.
> BIP/BOP box's used only on 40m and 6m..in most cases.
>
> later...... Jim VE7RF
>
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