I think it's time to pull Q100 and Q200 out and test them. I have found that good quality desoldering braid works. The cheap stuff is a waste of time.
C3 is part of the bias supply filter capacitance and C2 is doing the main work, so you can try whatever you have for C3.
A couple of questions:
- I inherited a bunch of electronic equipment and such from my late grandfather's workshop. Including a solid copper chassis from an old RCA voltage amp. No reason not to use this for a B1, right?
- I've cascaded three film caps together for C101/C201. What's the most elegant way to get a thick cap lead(s) to fit into a typical hole on a circuit board? Clip some of the strands until it fits through? Solder on a single copper wire? (I've done the former but am open to other techniques.)
Thanks
- I inherited a bunch of electronic equipment and such from my late grandfather's workshop. Including a solid copper chassis from an old RCA voltage amp. No reason not to use this for a B1, right?
- I've cascaded three film caps together for C101/C201. What's the most elegant way to get a thick cap lead(s) to fit into a typical hole on a circuit board? Clip some of the strands until it fits through? Solder on a single copper wire? (I've done the former but am open to other techniques.)
Thanks
Most elegant? And no pics for inspiration? If it's stranded, slip some heat shrink over the whole lead back to the cap body, so you can't tell how much you trimmed it.
I would have been tempted to use 'chicken head' knobs just fot the fun of it 
I tried searching but probably used the wrong terms. Are there any issues running a b1 buffer with +40 v b+? Any changes to optimise?
you can, but only if you cascode it, from both sides
then , there are several ways of, practically, introducing additional voltage regs for buffer rails
what voltage swing you're demanding from buffer, in that scenario?
then , there are several ways of, practically, introducing additional voltage regs for buffer rails
what voltage swing you're demanding from buffer, in that scenario?
Swing would be about +-10 can't be any more than +-15v. Here is a quick scheme of what I was thinking. Is there a link to a cascode b1?
Attachments
Hi everyone - just wanted to tell you that I found the cause of my problem. Turns out D1 was not working. Once I changed it for a new one it works fine. Wrong bias thus. Thanks for all the helpful suggestions.
Would it be a good idea to use a transformer output instead of the capacitor (on the ver1 of B1)
I ask because I've got two of 600-600ohm signal transformers.
I always liked the idea of using transformers because of the ability to impedance match, but a lot of people talk about loss of bandwidth etc.
Thanks
I ask because I've got two of 600-600ohm signal transformers.
I always liked the idea of using transformers because of the ability to impedance match, but a lot of people talk about loss of bandwidth etc.
Thanks
Thanks for the reply. Would it be the same value of capacitor?
Would there be any benefits from using the transformer?
Would there be any benefits from using the transformer?
see Papa's VFet amps article, from few days ago, there is exact example
benefits - gain
if you need gain and want to make it Kosher (without cap), look for B1T and Iron Pre
though, sound-wise, some even prefer with cap in circuit
benefits - gain
if you need gain and want to make it Kosher (without cap), look for B1T and Iron Pre
though, sound-wise, some even prefer with cap in circuit