If in doubt, grab the schematic. I find Fender always include extras like the pedals guts as well!

http://www.fender.com/support/amp_schematics/pdfs/Deluxe_112_Plus_Schematic.pdf

Quote from: J M Fahey on October 19, 2009, 04:25:45 AM
now you have a beautiful enclosure+speaker+power supply waiting for your chipamp.
What does the transformer supply?

Jm, I love your optimism!!

I'm still pondering over my Rock Pro but have considered several times of the possible salvage benefits!

93greenstrat,

If I get to the bottom of it i'll let you know.
Are you having the same problem with the selection switch?

I've managed to identify that the guy that last looked at the amp did botch the paths as the circle I identified shouln't have been connected at that point.

I haven't had the chance last week to do anything/look further as I've been swamped with work but the Mrs is now nagging me to clear the dining room table so I better get back on it!

Thanks J M Fahey, I guess I should concentrate on just getting the amp working first eh?!??!

ST Dog, you're right, the power supply goes straight through to that part of the board. I managed to strip the solder off and there definitely wasn't a path there before the "Boston Solderer Massacist" started his plight.

I cleaned it up to the degree of keeping the point and adjacent track seperate. I still need to chek that there is a circuit running through each of the "modified" tracks but apparently I was interupting the Mrs' TV. I'm not sure if the reverb works and I have to be honest.... after being shocked several times by the amp.... i'm not overly eager to plug something in to try it.

JM Fahey, I'm not sure that he has replaced a diode. The rest of the soldering on the whole board (except for the volume pot) seems to look very neet and untouched. Well spotted btw on the track in the pic though I'm afraid it is purely a very small drop of flux that didn't allow the light to reflect. I've checked the rest of the board and I'm pretty sure that there aren't any others.

Please forgive me for sounding "slightly simple" here (I've read some of your other posts!!) I am by nature a sound tech. I re-wire plugs, jack sockets, refit the odd speaker in a monitor here or there when a guitarist drops his pint on stage and generally sound check/mix all night long. The bigger in depth electronics is new to me and I'm learning as I go.

When you say:

Quote from: STDog on August 31, 2009, 01:06:05 PM
Then check TP30 and TP31 for the levels given on the schematic.
Since the LED is not working, I suspect them to be bad.

But maybe TP30 is good, and the problem is U8 or related components like CR39 & CR40, or R122 & R123.

Do you mean a continuity test to see that the circuit does continue through them or do you mean a voltage test to see what is going through them? Any extra tips on testing would be very helpfull and seriously appreciated.

Many thanks, Ronnie

Hi guys, thanks for coming back.

I've taken a couple of pics and had the chance over the last couple of days to have a closer look.

The first pic is the abbortion that he's made on the soldering job.... (Remeber, this guy is supposed to be a professional!!)



It looks like he's seen a break/soon to be break on the board and he's tried to patch it by re-routeing the paths with lines of solder. The pic looks like the board has burn out around that area, in fact... it's copius amounts of flux that he's used.

The next pic is a close up of where I believe the problem to be.



The arrow points to 2 "blobs" of solder that I don't think should be connected. The left part of the blob is the lower solder for component CR30 where the right blob looks like he slipt and didn't clean it up. This part of the circuit shouldn't join. To emphasise this, the next pic shows the opposite side of the board where the component can bee seen away from the path  of the adjasent curcuit.



I'm thinking (and hoping) that if I remove the excessive solder and break this connection that souldn't be there then I may be in luck.

I don't know if I'm thinking ahead here, but I read in another post on this forum that the rock pros send a current to the foot pedal and is intelligent to read the current coming back as to the selection of the pedal. Looking at the schematics for the pedal, I assume that using different resistors to limit the current for the reverb and OD channel gives the various combinations. As my amp seems to be "unable to decide" what channel to use, I am assuming that this is the part of the board that has been screwed up.

I know that keeping an old post going isn't cool but I had a further question regarding using the reverb channel for effects.

http://www.studiosoundelectronics.com/ampkits.htm sell a Fender® Gain Boost Cable
Stock No: GBC-1 for $9.95.



Can/could this be used in a rock pro 700 (if I ever get it fixed that is). Would be great to use this as an extra punch for lead work as I barely ever use reverb.

Many thanks,
Ronnie

Hi everyone.... I'm new here so.... I'm Ronnie, I live in Kent, Uk. Nice to meet you all.

Funny little story:

I took my amp into a sparkie's a while ago for problems with the volume pot. The clean channel's volume was really unstable, raising and dropping randomly. He ordered a propper Fender pot from the states and had it shipped back to the UK, replaced it (and the worrying part) never charged me. When I went to pick it up, he seemed to have forgotten all about the volume pot and said "I've looked at your amp. There was a little bit of a loose solder connection so I just resoldered it for you."

He was a little on the old side, and I have a feeling he may have been missing 1 or 2 of his marbles. He didn't charge me as he said the solder wasn't worth the effort of opening the till and said see how the amp goes.

The problem.... I then moved 130 miles away a couple of weeks later and never had time to use the amp (I know I should have checked but I had a lot on with moving). This was 6 years ago!! (I've been using my old 30 watt practice amp in this time as it's small and more friendly for the neighbours.) I've just been asked to join a band and start gigging properly again and the amp is (for lack of a better word) BUGGERED!

When you turn the amp on, the overdrive channel light is on, even when the amp is on the clean channel. When you press the button for the overdrive channel, the light stays on.... and the amp stays on the clean channel. I would have worded that to say that nothing happens.... but something does. A very painful electric shock through the finger.

I've taken the amp apart and there's a massive wadd of solder underneath where it looks like the circuit on the board was cut and he's piled solder on to replace the board's paths.

I know he must have crossed a path here somewhere but although I can locate this on the diagram that came with the amp, this is a little over my head!!

PLEASE SOMEONE HELP!!!

Sorry this was so long.