[Collins] 32V-1

[Garey Barrell]

There is one type of Dow-Key relay that has a second break contact 
inside the "receiver"  or NC side of the relay.  It can be recognized 
because the receive side connector is longer than the transmit side.  I 
have seen instances where the "longer" connector has been screwed 
further into the relay body to "make it even", which can actually 
compress the two fixed contacts around the armature contact.  Makes the 
"relay" into a "tee" connector!  Perhaps the relay in question had been 
"adjusted" to a very close spacing and contact erosion led to a short.?

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B & C-Line Service Supplement CDs
<www.k4oah.com>



Sheldon Daitch wrote:
> I suppose depending on the failure mode of the relay, it could
> have connected the TX to RX terminal.
> How?
>
> Real mechanical failure due to the breakage of moving parts
> inside the relay.
>
> I know we generally think of relay failure as coil related,
> but other parts of the relay can break and short the poles
> in ways a normally operating relay cannot connect.
>
> 73
> Sheldon
>
>
> Jim Brannigan wrote:
>
>> If the relay failed to energize, how did the TX terminal connect to 
>> the RX terminal?  At worst the TX would transmit into an open load...
>>
>> Jim
>>
>>
>>> The 75A1 uses a common input transformer/coil on all bands. The 
>>> secondary is fed to the individual band coils.
>>>
>>> Bad DowKeys is one reason I switched to a regular open frame relay 
>>> ages ago for my boatanchors. If the VSWR is high up on 10M its easy 
>>> enough to tune out with a compression trimmer at low power, measure 
>>> and then replace with a 1KV mica or disc for up to several hundred 
>>> watts.
>>>
>>> Carl
>>> KM1H
>>>