Rickresource Rickenbacker Forum

Hi guys

I have been using my bassman now for a couple of full blown rehearsals now and it sounds really nice, watch those guys with bassman effects pedals drool :D .

The only weird thing is that when i try to switch the amp on, it doesn't come on. I sometimes have to flick the power switch about ...

Thats it guys, you have hit the nail on the head :lol: .

I changed the suspect cap last night and it sorted it, luckily i had a spare silver mica cap. I think i will replace it with a ceramic one sometine soon.
I am going out tonight for a band rehearsal, so i should be able to give it a good blast ...

Hi greg,
i have been checking my amp circuit for DC voltage on the pots and i found lots, here are my results. I have taken the readings from all the pots testing from pin 1 to pin 3 from left to right facing the front of the amp :
V1: 1=0, 2=0, 3=0
T: 1=222.2, 2=119.7, 3=77.0
M: 1=(no connection ...

Hi Greg,
Thanks for getting back to me :mrgreen:
Yes my channel 1 still has scratchy pots, thats the volume, bass, mid and treble. The channel 1 volume only makes the scatchyness louder.
There is a constant back ground noise when the pots are not being turned and it does this whether an instrument ...

Well i spent the weekend measuring, marking, drilling and fixing new tube rivets to my new epoxy fibre board.

I meticuously removed every component from the old fibre eyelet board and transferred to my new afore mentioned board.
Connected it all back up to the input/ outputs and it is exactly the ...

This occurs where the fiber eyelet board - which is waxed to keep out moisture, but often not very well - begins to degrade and develop very slight conductive paths through the material which like all organic substances is carbon-based. You won't be able to measure the resistance - it's extremely ...

I have found the turret boards available on TAD, do you know which circuit or style i would need? Whatever is the correct one for the amp circuit model you have. You could probably adapt one that's close, if you can't find the exact one - or be more creative, and "de-evolve" the amp to an earlier ...

I have a Silverface Bassman 70 here with the same problem - not just scratchy when turning the pots, but constant pop-and-crackle background noise too, only on the Bass channel. There is some slight measurable DC on the tone stack, but not much. I've tried changing the coupling caps, of course. It ...

Mine does sound the same as the normal (channel 2) side is virtually silent, all the pots are silent when moved, but the Bass instrument (channel 1) side is very noisy when static and all the pots are scratchy when moved.
Which is the coupling cap, what is it's value? the only reason i ask is that i ...

One more thing;
i am thinking of having the transformers re-wound.
Has anyone else had this done?
Is there any transformer scematics available?

Hi
i have finally got all of my pars changed.
I ended up fitting a full set of pots, volume, and tone.
The weird thing is channel 2 sounds pretty much silent (no background noise or interference) but channel 1 is still very noisy (permaneant background noise and made worse when the tone pots are ...

Thanks for all your advice guys.
I have the last few parts now and i am planning on getting it finished this weekend.
I will give it a test after this and let you know the outcome.
Cheers
martin

Just another quick question.
I have had to remove all the old tolex as the wooden cabinet was falling ...

Hi Greg
Thankyou for the information.
So are the heater wires the grey twisted wires running to all the tube plates?
What colour are the grid wires?

Hi Greg
is the twisted wire arrangement the wires shown in 06-141-8.jpg. What other ways are there to sort out the oscillation.

For the heater and grid wires; is there some kind of shielding that can be done to keep them seperate.

thanks

martin

thanks for the diagnosis sharkboy.
i am awaiting a couple of parts from TAD, namely a capacitor, some resistors, deoxit d5 and a new bright switch.
After i have done these last few mods i will fire it up again............ fingers crossed no hum.
Anyone else got any ideas looking at my uploaded ...