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Hoffman Amps Forum image Author Topic: Fender Deluxe Output Transformer testing  (Read 3900 times)

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Offline fritz203

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Fender Deluxe Output Transformer testing
« on: March 20, 2022, 03:43:00 pm »
I tried to search for this topic, but couldn't find anything relevant.
Is there a way to test a Fender output transformer but just measuring the input/output winding ohms(not impedance)?
Thanks

Offline Kaaskop

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Re: Fender Deluxe Output Transformer testing
« Reply #1 on: March 30, 2022, 06:39:40 am »

Offline Latole

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Re: Fender Deluxe Output Transformer testing
« Reply #2 on: March 30, 2022, 07:20:02 am »
I tried to search for this topic, but couldn't find anything relevant.
Is there a way to test a Fender output transformer but just measuring the input/output winding ohms(not impedance)?
Thanks

No.
Only if windings read open you'll know it is bad.

Why do you want to test it ? What's wrong with the amp ?
« Last Edit: March 30, 2022, 07:23:25 am by Latole »

Offline shooter

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Re: Fender Deluxe Output Transformer testing
« Reply #3 on: March 30, 2022, 10:04:06 am »
Quote
input/output winding ohms
you'll want a good meter that can "zero" out probe errors since some of the readings will be in sub-ohms
Went Class C for efficiency

Offline fritz203

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Re: Fender Deluxe Output Transformer testing
« Reply #4 on: March 30, 2022, 02:58:11 pm »
Ok, thanks for all your help, that is what I was looking for. 

Offline Latole

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Re: Fender Deluxe Output Transformer testing
« Reply #5 on: March 30, 2022, 03:06:47 pm »
Ok, thanks for all your help, that is what I was looking for.


Why do you want to test it ? What's wrong with the amp ?

Right DC resistors do not mean transformer will work / sound fine
« Last Edit: March 30, 2022, 03:16:25 pm by Latole »

Offline fritz203

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Re: Fender Deluxe Output Transformer testing
« Reply #6 on: March 31, 2022, 10:16:22 am »
I figured out the transformer is fine, that was just a part of the troubleshooting. I had a screen resistor burn out and that took out the output tubes, so I wanted to check the transformer also. It turns out I had the output tubes biased too hot. All is fixed now. Thanks.

Offline Latole

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Re: Fender Deluxe Output Transformer testing
« Reply #7 on: March 31, 2022, 10:24:38 am »
Good news !

What is the amp we are talking about ?

Offline Latole

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Re: Fender Deluxe Output Transformer testing
« Reply #8 on: April 01, 2022, 05:25:59 am »
Useful ?


Offline pdf64

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Re: Fender Deluxe Output Transformer testing
« Reply #9 on: April 01, 2022, 06:35:53 am »
A 'hard' fault on a push pull OT primary may be revealed by comparing the full primary resistance to the sum of the CT to anode resistances.
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Offline PRR

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Re: Fender Deluxe Output Transformer testing
« Reply #10 on: April 01, 2022, 01:58:57 pm »
RG Keen has a transformer shorts tester.

« Last Edit: April 01, 2022, 03:03:41 pm by PRR »

Offline Latole

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Re: Fender Deluxe Output Transformer testing
« Reply #11 on: April 01, 2022, 02:59:31 pm »
RG Keen has a transformer shorts tester.

Him ?

R.G. Keen
Cheif Engineer
Visual Sound
www.visualsound.net

Offline PRR

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Re: Fender Deluxe Output Transformer testing
« Reply #12 on: April 01, 2022, 03:04:45 pm »
Yes but no. His personal site Geofex. http://www.geofex.com/  http://www.geofex.com/ampdbug/outtrans.htm
 

Offline Latole

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Offline fritz203

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Re: Fender Deluxe Output Transformer testing
« Reply #14 on: April 04, 2022, 03:40:11 pm »
Ok, thanks again.

 


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