Larrchild
Well-known member
get the 47uf instead.
Vintage valve radio into valve guitar amp
- Thread starter datape
- Start date
Help Support GroupDIY Audio Forum:
okay i found the missing cap.... its in the same package as one of the 16uf. I took it out of the clamp to check its value as the circuit wasnt making sense the way it was wired and the case said
RED 16
YELLOW 8
CASE ground
so its a double capacitor i guess.
I powered the thing up. I can hear guitar thru it, but its not loud enough. I can turn the volume up only so far before it starts making bad humming noises. I may have got some thing mixed up somehere with the capacitor confusion as I pulled a few wires here and there, but have put everything back as I remeber them. but i'm thinking it may not be worth spending more time on? I dunno any suggestions?
RED 16
YELLOW 8
CASE ground
so its a double capacitor i guess.
I powered the thing up. I can hear guitar thru it, but its not loud enough. I can turn the volume up only so far before it starts making bad humming noises. I may have got some thing mixed up somehere with the capacitor confusion as I pulled a few wires here and there, but have put everything back as I remeber them. but i'm thinking it may not be worth spending more time on? I dunno any suggestions?
Larrchild
Well-known member
Take some voltage readings now on the plates of the tubes. Tell us the voltages you get.
Larrchild
Well-known member
Perhaps it has been bad all along here and we are just finding that out.
Move the tone control pot. See if that helps.
Move the tone control pot. See if that helps.
I have been looking at redesigning the circuit so that I can completely undertsand what is going on...
I stumbled across STC's
http://www.gem.hi-ho.ne.jp/katsu-san/audio/what_STC1_english.html
can these valves be rewired in this configuration?
I stumbled across STC's
http://www.gem.hi-ho.ne.jp/katsu-san/audio/what_STC1_english.html
can these valves be rewired in this configuration?
> can these valves be rewired in this configuration?
"Bull in a china shop" comes to mind.
The amp worked.
It didn't have enough gain for the new purpose, so I gave you a few changes.
You stayed up late and ripped everything out.
Next day you couldn't figure out where anything was. If you'd gone one step at a time, and left all "useless parts" in place, you would not have has to trouble larchild for explanation of tube sockets: simple cross-checking would have found the right pins.
It isn't working now. You bungled something.
So, having reduced it to a wreck, you want to finish the job.
With one of those utterly strange designs that IMHO makes little sense, and NO sense for a darn Guitar Amp!
The Basic Radio, and the Basic Guitar Amp, are the same thing except one extra preamp stage.
> so that I can completely undertsand what is going on...
FWIW, _I_ don't understand that STC amp.
Basics, not esoterics.
Can you un-do the mess you made? Or is it beyond salvation?
What is your supply voltage, your plate voltage, your plate current on the output stage? Output transformer trouble is almost certainly there, if you'd just chill-out and look.
"Bull in a china shop" comes to mind.
The amp worked.
It didn't have enough gain for the new purpose, so I gave you a few changes.
You stayed up late and ripped everything out.
Next day you couldn't figure out where anything was. If you'd gone one step at a time, and left all "useless parts" in place, you would not have has to trouble larchild for explanation of tube sockets: simple cross-checking would have found the right pins.
It isn't working now. You bungled something.
So, having reduced it to a wreck, you want to finish the job.
With one of those utterly strange designs that IMHO makes little sense, and NO sense for a darn Guitar Amp!
The Basic Radio, and the Basic Guitar Amp, are the same thing except one extra preamp stage.
> so that I can completely undertsand what is going on...
FWIW, _I_ don't understand that STC amp.
Basics, not esoterics.
Can you un-do the mess you made? Or is it beyond salvation?
What is your supply voltage, your plate voltage, your plate current on the output stage? Output transformer trouble is almost certainly there, if you'd just chill-out and look.
thanks for your help previous PRRR.....
But I've lost patience with this amp.....
Besides I don't like your tone. If Larchild chose to help me then I dont count that as me troubling him. I didnt direct the questions at anyone specific. He answered. I said thankyou.
I think you need to chill out.
MOO!! FWIW
But I've lost patience with this amp.....
Besides I don't like your tone. If Larchild chose to help me then I dont count that as me troubling him. I didnt direct the questions at anyone specific. He answered. I said thankyou.
I think you need to chill out.
MOO!! FWIW
Larrchild
Well-known member
I liked the cool look of that unit. And thought it would make a swell practise amp or recording amp because of it's novel character and 30's tubes. So, I jumped in and started you on this path, because it's a fun thing to take a 30's or 40's radio and play guitar through it.
But when all of that effort was met with answers from you that didn't match my questions, and a desire to re-do the whole thing, instead of changing 4 parts, like PRR suggested, when he got involved, it has now amounted to disapointment in both of us.
But some other people have read it now, and want to start tube projects. So it's not a loss.
What PRR said is completely accurate from my perspective, also. and going after him is poor judgement.
Good Luck.
I dont want to to argue and appreciate everyones help on all fronts. And I certainly aint going after anybody here mate.
Its very sad that things have been interpreted this way. I was going to leave this thread to die a death when I read the response, but was troubled by the arrogant answers from the 'moderator'.
If I stepped on an ego by asking about something that is beyond the scope of this thread and peoples knowledge, then sorry..?? All it takes is telling me in a civil manner, not with humiliating and arrogant tones.
I wasnt ignoring any questions and was going to return with answers. STC was a subject that came up as I looked at more circuits and hadnt seen this type before.
Thanks again for your time......
Dave
Its very sad that things have been interpreted this way. I was going to leave this thread to die a death when I read the response, but was troubled by the arrogant answers from the 'moderator'.
If I stepped on an ego by asking about something that is beyond the scope of this thread and peoples knowledge, then sorry..?? All it takes is telling me in a civil manner, not with humiliating and arrogant tones.
I wasnt ignoring any questions and was going to return with answers. STC was a subject that came up as I looked at more circuits and hadnt seen this type before.
Thanks again for your time......
Dave
Similar threads
