Classictone PT for Bassman Clone - Wiring Questions

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ToneMerc
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Re: Classictone PT for Bassman Clone - Wiring Questions

Post by ToneMerc »

steves3972 wrote:Thanks TM, did you mean brown/white to neutral rather than black/white?
yep, corrected
steves3972
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Re: Classictone PT for Bassman Clone - Wiring Questions

Post by steves3972 »

I’ve been trying to finish the build using the ceriatone 5f6a layout using classictone transformers.
I am getting very low voltage readings at all tube sockets.
I have double checked that all the resistors on the board are the correct value and tested all of them. But I am still losing voltage somewhere.
There is a 100k resistor on the standby switch and I am not sure of it’s purpose. On one side of the standby switch I was getting 400volts then on the other side after the 100k resistor I was getting around 100volts. This doesn’t seem right to me.
Can anybody suggest what I need to do?
Many thanks
John_P_WI
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Re: Classictone PT for Bassman Clone - Wiring Questions

Post by John_P_WI »

All the 100k resistor is for is a soft start / pop reducer when the standby switch is flipped. IF your voltage is not rising when the standby switch is flipped either the switch is bad or you have the resistor in series with the switch not across the contacts. Just my guess....
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ToneMerc
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Re: Classictone PT for Bassman Clone - Wiring Questions

Post by ToneMerc »

steves3972 wrote:I’ve been trying to finish the build using the ceriatone 5f6a layout using classictone transformers.
I am getting very low voltage readings at all tube sockets.
I have double checked that all the resistors on the board are the correct value and tested all of them. But I am still losing voltage somewhere.
There is a 100k resistor on the standby switch and I am not sure of it’s purpose. On one side of the standby switch I was getting 400volts then on the other side after the 100k resistor I was getting around 100volts. This doesn’t seem right to me.
Can anybody suggest what I need to do?
Many thanks
I wired the same setup in my JTM45 clone with no issues. It's kind of hard to hose up, just cap & resistor set across the two lone switch terminals. Are you 100% sure it's wired exactly as depicted?

TM
steves3972
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Joined: Fri May 25, 2012 9:43 am

Re: Classictone PT for Bassman Clone - Wiring Questions

Post by steves3972 »

thanks
ok, so I've worked out that I need to have the amp completely on, not in standby mode to get proper voltage readings. everything is reading ok now, maybe slightly high.
Now the problem is that the amp has low output and slightly distorted, could be a number of things causing that. Bad tube, bad output tranny, wired input jacks wrong.

Not sure where to start...
steves3972
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Re: Classictone PT for Bassman Clone - Wiring Questions

Post by steves3972 »

here are my voltage readings, pin 1 & pin 4 on both 6l6s seems low to me, most of everything else seems a little high, not sure about pins 2 and 7 on the v3, looks like they're half of what they're meant to be as well.
v1
1.180
2.0
3.2
4.fil
5.fil
6.178
7.0
8.2
9.fil

v2
1.188
2.0
3.1.3
4.fil
5.fil
6.371
7.188
8.198
9.fil

v3
1.280
2.15
3.53
4.fil
5.fil
6.261
7.17
8.53

6l6
1.6.1mv
2.fil
3.494
4.330
5. -40
6.491
7.fil
8.6.1mv

6l6
1.6.3mv
2.fil
3.491
4.328
5. -40
6.489
7.fil
8.6.3mv
John_P_WI
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Re: Classictone PT for Bassman Clone - Wiring Questions

Post by John_P_WI »

Steve,

May I kindly suggest that you start a new thread to discuss this? It would be better.
steves3972
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Joined: Fri May 25, 2012 9:43 am

Re: Classictone PT for Bassman Clone - Wiring Questions

Post by steves3972 »

sorry, John. Will do. Hope I haven't annoyed you.
John_P_WI
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Re: Classictone PT for Bassman Clone - Wiring Questions

Post by John_P_WI »

Steve,

I kindly suggested to start a new thread to help you get more help and for people to be able to search this topic in the future as this has little to do with the Classic tone thread. Absolutely positive in both directions I hope, no hard feelings meant.
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