[R-390] break-in question, 390A and 390

[rbethman]

David,

That's one I can't answer.  I haven't had the opportunity to get my 
hands on one.

The Johnson T-R was hard enough to get!

Bob - N0DGN

On 7/24/2011 1:19 PM, David C. Hallam wrote:
> Mine is a B&W 381C.  I don't know if it is as robust as the Johnson.
>
> David
> KW4DH
>
> On 7/24/2011 12:38 PM, rbethman wrote:
>> David,
>>
>> I put the output of the BC-610 into it.  That's 400W carrier.  I DO 
>> get 100% modulation.  I actually have to dial things down to stay 
>> with the 1500W PEP.
>>
>> That T-R Switch is built like a tank!
>>
>> Bob - N0DGN
>>
>> On 7/24/2011 12:28 PM, David C. Hallam wrote:
>>> A T-R switch is a more elegant solution than two relays.  At the 
>>> time I set up the R-390, I did not have one.  I do now but am a 
>>> little hesitant about putting the output of my Invader 2000 into the 
>>> T-R switch.
>>>
>>> David
>>> KW4DH
>>>
>>> On 7/24/2011 11:42 AM, rbethman wrote:
>>>> Amen!  It took a bit to figure that one out.
>>>>
>>>> What was very startling, was to have the R-390A off the antenna 
>>>> switch with only about a 3 ft jumper of coax attached.  Somone 
>>>> across town lit up on the frequency and I swear the R-390A darn 
>>>> near jumped up!
>>>>
>>>> Yes - they ARE that sensitive!
>>>>
>>>> I've managed to eliminate the extra relay by using a Johnson T-R 
>>>> Switch, and using the break-in.
>>>>
>>>> I monitor MY signal AND the one I am listening to by picking the 
>>>> 455Kc off the rear and feeding it into a Kenwood SM-220 w/BP-8.
>>>>
>>>> Bob - N0DGN
>>>>
>>>> On 7/24/2011 11:33 AM, David C. Hallam wrote:
>>>>> The break in relay on the R-390 only grounds the antenna input and 
>>>>> does
>>>>> not mute the receiver.  What you have to do is open the RF gain
>>>>> connection on the back panel strip.  I did it with a relay.  On 
>>>>> transmit
>>>>> you ground the R-390 break in relay and open the relay in the RF gain
>>>>> circuit.
>>>>>
>>>>> David
>>>>> KW4DH
>>>>>
>>>>> On 7/24/2011 10:42 AM, frankshughes at aim.com wrote:
>>>>>> Hi,
>>>>>> I am seeking advice on break-in function and troubleshooting audio.
>>>>>>
>>>>>>
>>>>>> I have a Collins 32S-3 transmitter, and am trying to use either a 
>>>>>> 390A or 390
>>>>>> to receive.
>>>>>>
>>>>>>
>>>>>> I have deduced that the relay logic for the 32S-3 (Open w/ PTT) 
>>>>>> had to be reversed
>>>>>> to work with the "break in" contact on the 390A and 390 terminal 
>>>>>> strip (N.O.)
>>>>>>
>>>>>>
>>>>>> So I put a relay in the circuit between the 32S-3 and 390, works 
>>>>>> great.
>>>>>>
>>>>>>
>>>>>> The ohm meter shows that when I PTT the 32S-3, the 390A and the 390
>>>>>> antenna input center pin goes to ground, and the audio also 
>>>>>> squelches to full quiet.
>>>>>>
>>>>>>
>>>>>> However, I get lots of audio output from the 390A and the 390 
>>>>>> when I speak into the mic!!!
>>>>>>
>>>>>>
>>>>>> So even though the antenna input is grounded, both the 390A and 
>>>>>> the 390 are still getting
>>>>>> signal input.
>>>>>>
>>>>>>
>>>>>> The audio is also present from the 390 and 390A if I disconnect 
>>>>>> the antenna and activate break in
>>>>>> while keying the 32S-3.
>>>>>>
>>>>>>
>>>>>> Is the 32S-3 bleeding RF into the shack the 390 and 390A can pick 
>>>>>> up even with the antenna disconnected?
>>>>>> (How can these things be so sensitive to tiny RF levels...oh, 
>>>>>> wait....)
>>>>>>
>>>>>>
>>>>>> If so, building a Faraday cage around my transmitting position 
>>>>>> would be ....crazy.....OK, plan "B" is to
>>>>>> put a relay into the audio circuit to open the input to the 
>>>>>> speaker at the same time PTT is activating
>>>>>> break-in.
>>>>>>
>>>>>>
>>>>>> Or what else can I do????
>>>>>>
>>>>>>
>>>>>> Thanks,
>>>>>> Frank
>>>>>> KJ4OLL