On 7/8/2012 8:40 AM, Joe Subich, W4TV wrote:
>
> > Using double pole relays in binary trees is normally considered a very
> > unreliable way to go in industry.
>
> The RCS-10 does not use double pole relays - at least according to
> the schematic in the Instruction Manual. It uses seven SPDT relays
> connected with four, two and one coils connected to the A. B and C
> control lines respectively.
>
>> I have used the more conventional RCS4 and 8 that use the second set
>> of contacts on each relay to prevent any other relays being active
>> other than the one selected.
>
> Again, according to published schematics there are no "interlock"
> contacts in either the RCS4 or RCS8 relay units.
You are correct. I must have been thinking of the six-pack
> The RCS4 uses three
> relays in a binary (one feeding two) arrangement while the RCS8 uses
> five "form X" relays in a "star" configuration. The RCS-8 is designed
> specifically to allow multiple antennas to be connected simultaneously
> (paragraph 1, page 3 of the Instruction Manual).
Manual?
The RCS8 is just 5 DPDT relays that have the armature "bridged", or just
call it a common bridge.
It's a very simple arrangement of 5 relays hooked to a common buss and 5
control wires plus ground. The NO side of the relay can be bridged to
ground so the unused antenna can be grounded when not in use.
I don't know what is so corrosive around here, but any connectors that
do not have an antenna hooked to them, need one of those plastic caps
pressed over it/them or tape farther than a connector will thread on or
you will not be able to connect to it within a year. Particularly
silver and nickle dissolve right off the connectors. Plain heat shrink
or the tape that adheres/vulcanizes to itself needs to be used on the
connectors. Heat shrink is easier. I made a skirt to of plastic that
extends down a couple of inches to keep the connections out of the
weather but they still need to be protected. Without the skirt I'd use
flooded heat shrink.
73
Roger (K8RI) When all else fails, RTFM <:-))
>
> 73,
>
> ... Joe, W4TV
Thanks for bringing that to my attention Joe.
>
>
>
> On 7/8/2012 12:50 AM, K8RI wrote:
>> On 7/7/2012 11:00 PM, Joe Subich, W4TV wrote:
>>>
>>> > First question. I have an Ameritron RCS-10 that doesn't seem to work
>>> > on all positions. Mine only works on 1-4 with no connection on the
>>> > other positions. What would cause that? It almost seems like 2 and 6
>>> > are hooked together and 1 and 5 too!
>>>
>>> RCS-10 uses a "binary tree" arrangement of relays. You will probably
>>> find the input relay has been arced so that both the normally open and
>>> the normally closed contacts are connected at the same time (all the
>>> time).
>>
>>
>> Using double pole relays in binary trees is normally considered a very
>> unreliable way to go in industry. Solid state logic is much more
>> reliable and only takes 4 lines to count to 10 (BCD) and is simple to
>> decode with one chip. I can't imagine why anyone would use relays in a
>> binary tree. I've never seen an RS10 so I can't verify the
>> construction, but I have used the more conventional RCS4 and 8 that use
>> the second set of contacts on each relay to prevent any other relays
>> being active other than the one selected.
>>
>> 73
>>
>> Roger (K8RI)
>>
>>>
>>> > Second question is about the need/benefit of grounding coax cables at
>>> > the bottom of a tower.
>>>
>>> It's called lightning protection. You want the shield of all cables
>>> connected at both the top and bottom of the towers so that a lightning
>>> strike can't cause a high voltage between the tower and cable shield
>>> which would "puncture" the insulation and put the high voltage on the
>>> chassis of any connected equipment. There is a lot more in the literature.
>>>
>>> 73,
>>>
>>> ... Joe, W4TV
>>
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>>
>>
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