I have gone through 2 different RCS-10 units. Inspecting both, after
failure, shows
signs of arcing and or burning of the relays. At no time was more than
1 KW used.
I am now using RCS-8V units and have used them for more than 20 years without
failure. I much prefer their field tested results.
73,
Larry K4AB
On 7/8/12, K8RI <K8RI-on-TowerTalk@tm.net> wrote:
> 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
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>
>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|