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Hoffman Amps Forum image Author Topic: '69 Fender Bandmaster Reverb Capacitor Question  (Read 2096 times)

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Offline tomof63

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'69 Fender Bandmaster Reverb Capacitor Question
« on: February 24, 2021, 04:36:07 pm »
Hi All,

Recently purchased a mostly stock '69 Bandmaster Reverb. It had 2 prong plug and all original caps. I couldn't locate one of the capacitors a 25uf 25V in the vibrato circuit. According to the one and only layout diagram (thanks Hoffman!) it should have been on the main board. I finally located it, it was on pin 3 of V5 and connected to the sleeve of the vibrato jack. I should've taken a pic of it but I didn't. I pulled the old cap out and now I'm second guessing myself on the orientation of the polarity. Does anyone know if the + should be toward the pin or the sleeve of the vibrato jack?

Thanks in advance!!

Offline tomof63

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Re: '69 Fender Bandmaster Reverb Capacitor Question
« Reply #1 on: February 24, 2021, 04:45:17 pm »
Or should I just solder in a replacement capacitor on the board where it is shown in the layout diagram? I may have answered my own question. :smiley:

Offline jordan86

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Re: '69 Fender Bandmaster Reverb Capacitor Question
« Reply #2 on: February 24, 2021, 04:47:30 pm »
could you post your schematic or layout?

Offline jordan86

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Offline jordan86

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Re: '69 Fender Bandmaster Reverb Capacitor Question
« Reply #4 on: February 24, 2021, 04:52:19 pm »
Those original fenders often had a dual cap in that spot. Two caps inside one unit. Two positive leads but one negative to ground. If your replacing it with two individual caps you’ll have two separate negative leads to ground.

Offline tomof63

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Re: '69 Fender Bandmaster Reverb Capacitor Question
« Reply #5 on: February 24, 2021, 05:06:30 pm »
Yes that's the same schematic and layout.
It had just one white Mallory 25uf, not 2 in that position as is shown on the layout. I just don't remember which direction I should wire in a new one.

Offline 2deaf

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Re: '69 Fender Bandmaster Reverb Capacitor Question
« Reply #6 on: February 24, 2021, 05:22:57 pm »
Hi All,

Recently purchased a mostly stock '69 Bandmaster Reverb. It had 2 prong plug and all original caps. I couldn't locate one of the capacitors a 25uf 25V in the vibrato circuit. According to the one and only layout diagram (thanks Hoffman!) it should have been on the main board. I finally located it, it was on pin 3 of V5 and connected to the sleeve of the vibrato jack. I should've taken a pic of it but I didn't. I pulled the old cap out and now I'm second guessing myself on the orientation of the polarity. Does anyone know if the + should be toward the pin or the sleeve of the vibrato jack?

Thanks in advance!!

+ goes to pin 3 and - goes to the sleeve of the vibrato jack.

Offline tomof63

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Re: '69 Fender Bandmaster Reverb Capacitor Question
« Reply #7 on: February 24, 2021, 05:26:52 pm »
2deaf,

Thanks for the info! I had no doubt that some one here would know.


 


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