Messages

So, the scheduled smf weekly maintenance is still causing the forum to crash..specifically when smf tries to optimize the database. I dunno why. But, at least we are back for now. Sorry for the few hours down time...I thought this was happening tomorrow morning, not today.

The only problem is that adding more gain in that second stage could lead to some distortion. It depends on what the max "light" resistance is on the photocell you are using. If you find that a 25k pot results in distortion, put it back to 10k and make R13 470k or 680k instead.

PPP has them although they are more spendy.

It's definitely boned. Some of the pads have lifted. Too much heat and sucking, lol. You can send me another if you want. No big deal man. I can't wait to get that diode out so I can get this thing working, lol

Just PM me your current shipping info and I will send you the board. Are you able to get your other parts out of the other? I can send along a few resistors/caps if that is going to give you trouble.

D4-D6 and C20, C21 should be omitted ideally but the most important is omitting D5 and D6. I've corrected the doc. If you're first board is boned lemme know and I will send you a replacement...this was my fault.

On the 2015 doc, I forgot to say to omit D6 when building the project for using an 18v supply. I described how to build the 9v version and then described how to change it to an 18v supply afterward. This was dumb on my part. I have re-written that portion of the doc to describe exactly what to do in each case. This is what the doc now says:

For the 9v method populate everything on the board EXCEPT D3. You must leave this diode off for the voltage to come out correctly.
For the 18v method populate D3, and omit IC8, D4, D5, D6, C20 and C21.

You need to omit D6. This should have been in the document. I said to convert from 9v to 18v omit IC8 and remove/omit D5. But, I forgot to say to remove D6 as well! Sorry for my mistake...I will fix the doc.

Also, the entire bill was itemized with the cost of each part (plus the tax).

Awesome Brian. I have repaired many of these awesome little guys. They are always a worthy investment.
I would be curious what the total bill was for you. I like to know these things to help me better price my services (although I understand location is a big factor here).

It was $288. Their bench charge is $80/hr with 2.25 hrs charged for diagnosis and repair, plus parts, etc. Kinda spendy but not unreasonable. I paid only $200 for the amp to begin with.

Fixed Amp Day. After being broken for over a year I finally got the Silverface Champ fixed. I blew this puppy up pretty good a while ago. Pop, smoke, burning smell. I kept putting off dealing with it with the thought that I should be able to fix it myself. But, fixing something is quite a bit different than diagnosing the problem so I took it to a repair shop in Nashville. I'm glad I did because there were quite a few issues. Finally diagnosis - too much B+ blew the power tube. So, the dudes at Nashville Amplifier Service did the following:

Dropped B+ a bit, replaced the tube, replaced the tube sockets (really loose), filter recap, removed the death cap (was still there for some reason despite having a three prong), new fuse. Now she sounds as good as ever! Unfortunately, the total repair cost was more than I paid for the amp but my total investment now is on par with a perfectly working 70's era Champ so I'm cool with it (I got it cheap to begin with). Plus, I will never sell it. Only drag is the dead OS Ratheon tube. Sorry bro.

The Champ is pretty near perfect as a test amp for pedal designs, IMO. I'm so glad to have it back! And, the NAS guys were really great, too. Very friendly and knowledgeable.

Very cold temps could cause a joint to crack I suppose. Or, it could just be coincidence. The thing I would probably do first is look at your voltages around the LFO. If that looks right then maybe re-flow the solder on that area and the speed pot.

I've added the BlackRain SMF theme back. Since this was installed after some packages I do not know if all package features will show up properly, but it's there if you want to use it. "DarkModern" is the MBP default.

People are also more likely to post when they have a problem, as well. Hence the appearance of more non-working builds (goes for any project just about).

You are a frikkin maniac. Good jorb!

220k, 6k8 and 47R are fine. Small differences are just that. Maybe it could change the end result slightly but it certainly won't "hurt". You can use a 180k + 22k in series for a closer approximation of 200k. Similarly, 6k8 and 1k in series.