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Hoffman Amps Forum image Author Topic: Hoffman Fender Blues Junior Conversion  (Read 3176 times)

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Offline dand

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Hoffman Fender Blues Junior Conversion
« on: June 01, 2017, 02:27:09 pm »
I was thinking it would be nice to replace the LED with a Pilot Lamp, like a Fender Deluxe would have installed in the circuit on the Green filament wires, between the Power Trans and the Power Tubes.
Has anyone already tried it on this Blues Jr conversion? Is it a good idea or not and why?
Thank You

Offline EL34

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Re: Re: Hoffman Fender Blues Junior Conversion
« Reply #1 on: June 01, 2017, 02:41:27 pm »
It's fine if you can drill a giant hole in the chassis for a fender pilot lamp assembly

Offline dand

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Re: Re: Hoffman Fender Blues Junior Conversion
« Reply #2 on: June 10, 2017, 06:36:56 am »
Hello, I am hoping to find out some repair advice on my Blues Jr conversion.
Unfortunately, I made a mistake on the connection of the Treble pot and connected the center terminal to ground. The result was no sound when the amp was powered up. The error went undetected for about a minute. Later, when I made the correction I had sound and volume restored. However, when increasing the overdrive and then playing through the amp, the sound cuts out. When I power down the amp and restart, the volume returns but again will cut out when overdriven. I suspect I have damaged a component(s) from the initial hookup error on the Treble pot.
Any ideas where to start? Thank You !

Offline EL34

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Re: Hoffman Fender Blues Junior Conversion
« Reply #3 on: June 10, 2017, 06:44:01 am »
I moved your post to the main forum

Offline sluckey

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Re: Hoffman Fender Blues Junior Conversion
« Reply #4 on: June 10, 2017, 06:49:31 am »
Quote
I suspect I have damaged a component(s) from the initial hookup error on the Treble pot.
I doubt that. Recheck your wiring.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline EL34

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Re: Hoffman Fender Blues Junior Conversion
« Reply #5 on: June 10, 2017, 06:53:07 am »
Go here first
Looks like you missed the treble pot, so you may have missed other things also
http://el34world.com/Forum/index.php?topic=19361.0

Offline purpletele

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Re: Hoffman Fender Blues Junior Conversion
« Reply #6 on: June 10, 2017, 04:03:55 pm »
I am chasing a ghostly drop in power on my HoSo.  It is acting very similar to another issue on my 6v6 Plexi where it was dropping into half power after a small duration.

The latter issue was resolved with a new Treble Pot ironically.

I suspect I may have a similar issue with Billy, the new amp.

You may consider that the Pot may be faulty as an option on your Bjr

Offline dand

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Re: Hoffman Fender Blues Junior Conversion
« Reply #7 on: June 11, 2017, 05:19:42 pm »
a couple of bad solder joints on the pots was the problem. I have retouched all my solder work and the Amp works and Sounds Excellent! I really like this Hoffman blues jr conversion amplifier. Before I did this I was trying to sell the amp for about 6 months but now it's a Keeper.

Thanks for the help!

Offline purpletele

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Re: Hoffman Fender Blues Junior Conversion
« Reply #8 on: June 11, 2017, 06:20:20 pm »
a couple of bad solder joints on the pots was the problem. I have retouched all my solder work and the Amp works and Sounds Excellent! I really like this Hoffman blues jr conversion amplifier. Before I did this I was trying to sell the amp for about 6 months but now it's a Keeper.

Thanks for the help!


Terrific!  What a good feeling.

BTW, I bought a couple of Mojotone's Blues Junior cabinets and they are really an asset to the Blues Junior amp from a resonance and tonality standpoint.  I was very surprised and now I insist for nice combo cabinets.

Offline EL34

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Re: Hoffman Fender Blues Junior Conversion
« Reply #9 on: June 12, 2017, 06:34:05 am »
a couple of bad solder joints on the pots was the problem. I have retouched all my solder work and the Amp works and Sounds Excellent! I really like this Hoffman blues jr conversion amplifier. Before I did this I was trying to sell the amp for about 6 months but now it's a Keeper.

Thanks for the help!


Good deal
Going over the amp layout diagram, point to point, with a colored marker is the best way I know of to figure out what you did wrong when assembling

 


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