[TenTec] RESOLVED: Centurion amp no output, was working

[Mike Cumbo]

Hello Jim,

 Be very careful with the high voltage in that amp! Make sure your probe is suited to the high voltage. I would check at the K contact on the parasitic suppressor board just near the plate caps on the tubes. You will have to disable the safety bar that grounds the HV when the top cover is removed, just rotate it away from the HV contacts, the cover won’t go back on until you put it back in place when finished. If your probe has a tip with an alligator tip or some type of gripping contact, use it. Make sure your ground contact is making good contact and can’t accidentally fall loose. I try to have both the probe and ground connected so I am not touching anything, then turn the amp on. Please be very careful, the voltage you are dealing with is lethal! If you are not comfortable dealing with the HV get someone to help you who is. BE CAREFUL! And good luck.

73, Mike Cumbo, ND4S




Sent from Mail for Windows

From: jkauppila--- via TenTec
Sent: Wednesday, March 15, 2023 5:57 PM
To: Discussion of Ten-Tec Equipment
Cc: jkauppila at tutanota.com
Subject: Re: [TenTec] RESOLVED: Centurion amp no output, was working

HI Mike,

You know, I was rereading the manual the other night and noticed the same thing and thought about what you said.  Oh well, either way I spotted it and got it out from being pinched.

On another note, this is probably something an amp veteran would know, but can you tell me where to measure the plate voltage?  The meter reads low, about 2,600-2,700V and I think the meter just needs to be adjusted as the amp seemed to put out proper power.  I do have a high voltage probe for my Fluke meter which would be able to handle the voltage.  If it is just the meter that's off, I have the meter adjustment information.

73, 

Jim 
AE1CW
-- 
 Sent with Tutanota, enjoy secure & ad-free emails. 



Mar 14, 2023, 21:18 by mcumbo at triad.rr.com:

> Hello again Jim,
>
>  My aging memory failed me. A look in my Centurion manual shows the tubes were shipped separately but it says nothing about the transformer being shipped separately or having to be installed. I falsely accused the original owner! My mistake and I admit it. I have still done worse!
>
> 73, Mike Cumbo, ND4S
>
>
>
> Sent from Mail for Windows
>
> From: jkauppila--- via TenTec
> Sent: Sunday, March 12, 2023 3:53 PM
> To: jkauppila--- via TenTec
> Cc: jkauppila at tutanota.com
> Subject: Re: [TenTec] RESOLVED: Centurion amp no output, was working
>
> The amp is now working.
>
> I opened it up and found a couple of connectors that were a bit loose and reseated them.  I also found something a bit more serious.  One of the hot 220V leads from the fuse was pinched under the transformer frame between the frame and the base of the cabinet.  It actually broke the insulation and there was bare copper showing.  I loosened the bolts under the cabinet for the transformer and lifted it enough to get the wire free to suspend it in free space.  I'll have to do some disassembly to get in to the wire and insulate it properly.  This amp was made in April 2010.
>
> I wanted to post this follow up so that no one wastes time on replying.  I'm not sure what it was, but it's fixed now.
>
> 73,
>
> Jim AE1CW
> -- 
>  Sent with Tutanota, enjoy secure & ad-free emails. 
>
>
>
> Mar 12, 2023, 10:25 by tentec at contesting.com:
>
>> I mistakenly transmitted from my Kenwood TS-590S into my new (used) Ten-Tec Centurion amp without the control relay turned on in the radio.  The amp saw up to 20 watts in with the amp switch in operate with no transmit relay signal from the radio.  Now the amp has no output.
>>
>> Notes:
>>
>> Amp turns on, standby, operate and transmit lights works.  There is plate voltage.  The tubes light.  There is plate current and grid current when I transmit from the radio with the radio's amp control relay now turned on, but no output from amp.  I only tried transmitting with low power from the radio, up to 25W.
>>
>> Could I have blown a component on a board transmitting into the amp when the amp switch was set to operate with no control signal coming from the radio?  If so, where should I look in the amp?
>>
>> Thank you for any suggestions.
>>
>>
>>
>>  
>> _______________________________________________
>> 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
>

_______________________________________________
TenTec mailing list
TenTec at contesting.com
http://lists.contesting.com/mailman/listinfo/tentec