[TenTec] Centurion 422 amp keying issues

[Bob McGraw K4TAX]

Although I've not researched my documentation on the topic, I do recall 
that one must jumper D2 on the QSK board to assure that the amplifier 
would key correctly from the Omni VII.

As to release of the T/R relay, if Q4 on the QSK board is leaky or is 
not turned off by U2 then the T/R relay will stay engaged. This will 
require a bit of trouble shooting on the QSK board to determine the 
exact cause as to why the T/R relay is being held engaged.  Also, the RF 
Sense transistor, Q3, being defective will command the T/R relay to stay 
closed, even after RF is removed.

To my knowledge, there are no replacement boards available for the 
Centurion series.

73

Bob, K4TAX


On 8/17/2018 5:15 PM, Jim Carragher wrote:
> Tom
> I had the same problem when I went from my Omni VI Plus to my new at the
> time, Omni VII. Would not unkey. Sent the Omni VII back to Ten Tec, Paul
> Clinton advised me to add a jumper across D2 on the QSK board. That was
> October 2014. Did as instructed and no problems since. I had to remove
> attached drawings from previous e- mail as file was too big. Hope this
> helps.  Jim K7IKN
>
> On Fri, Aug 17, 2018 at 2:31 PM, Jim Carragher <k7ikn2 at gmail.com> wrote:
>
>> Tom
>> I had the same problem when I went from my Omni VI Plus to my new at the
>> time, Omni VII. Would not unkey. Sent the Omni VII back to Ten Tec, Paul
>> Clinton advised me to add a jumper across D2 on the QSK board. That was
>> October 2014. Did as instructed and no problems since. Attached is Invoice
>> and drawing sent to me by him.  Hope this fixes it for you.  Jim K7IKN
>>
>> On Fri, Aug 17, 2018 at 1:03 PM, Bob McGraw K4TAX <rmcgraw at blomand.net>
>> wrote:
>>
>>> Centurion does as well.   Relay hanging up is most likely a component on
>>> the QSK board.
>>>
>>> Bob, K4TAX
>>>
>>>
>>> Sent from my iPhone
>>>
>>>> On Aug 17, 2018, at 3:02 PM, Jim Brown <k9yc at audiosystemsgroup.com>
>>> wrote:
>>>>> On 8/17/2018 12:44 PM, Barry N1EU wrote:
>>>>> Actually, I think it used an open-frame relay.
>>>> Could be -- I've never seen a Centurion. All the Ten Tec amps I've
>>> owned (Herc I, Herc II, Titan 425s) use vacuum relays.
>>>> 73, Jim K9YC
>>>> _______________________________________________
>>>> TenTec mailing list
>>>> TenTec at contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/tentec
>>>>
>>>
>>> _______________________________________________
>>> TenTec mailing list
>>> TenTec at contesting.com
>>> http://lists.contesting.com/mailman/listinfo/tentec
>>>
>>
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>