What to do with a brokem Memory Man Deluxe?

[Mark Abbott]

I have recently found that my trusty old Memory Man Deluxe reissue (5 knob), has stopped working. That it to say that I get an output from the echo out jack, but there is no echo chorus etc. Not a good thing in an echo pedal!

I suppose the first question to ask is what are the common faults associated with these units?

What recommendations would you make concerning the MMD?

I'll keep it brief so as to keep an element of open ended-ness to it all.

Yours Sincerely

Mark Abbott

P.S. yes I know ended-ness isn't a word!

[Toney]

1/ Start with mechanical problems (switches/pots) and broken wires.
2/ Check power is getting where it needs to be and grounding points
3/ Get audio probe. Probe!

[Mark Abbott]

Dear Toney

Thanks for the reply.

Power is getting to the unit as the power LED is working and audio is making it from the input jack through to the echo output jack.

There are no broken wires, I don't think there are any broken switches, switches can often be intermittent before they give up the ghost. I haven't yet reseated the IC's, but it is worth a go.

I don't think an audio probe will achieve a lot, I could be wrong though.

Yours Sincerely

Mark Abbott

[Pedal love]

  I don't think there are any broken switches, switches can often be intermittent before they give up the ghost. 
Yours Sincerely

Mark Abbott

CHECK THE SWITCHES!

[Mark Abbott]

Okay, I'll check the chorus/vibrato switch. The power switch works as the power led goes on and off.

Thanks for the advice.

Yours Sincerely

Mark Abbott

[Toney]

Seriously Mark, dig a little deeper, mate.
The Led coming on means very little.
Get out Mr Multimeter and start probing for power at the points in the schem where it's indicated.
But first, check  continuity  with the mechanical parts (most likely to fail)

Cheers, Toney

[Mark Abbott]

Dear Toney

Thanks for your reply. Your point is well taken, never assume anything with electronics. I should have explained the fault a little better.

I turn the MMD, the LED is shining, the overload LED flashes when I strum really hard. On my MMD the direct out and the input are wired together.

The echo output switches between the output of the first IC (IC1a) and the blend pot. I don't hear any difference when depressing the footswitch switch. I suppose the fault could be due to the footswitch, but I have a faulty (Carling) footswitch in my wah pedal. I get no output at all when I turn the wah on (it is an intermittent fault), but when I jiggle the switch the wah works.  I dare say I'll try another Carling switch in the wah pedal and hope for the best, but as this the second Carling switch to behave in this way, an alternative switch is looking favorable.

Back to the MMD. The only pot that works on the MMD is the level pot, should I turn the blend pot from side to side, it has no effect on the output of the guitar at all. I hear the guitar with no echo. To my way of thinking, I look at the circuit and all but two IC are wired in series. If I had a shorted IC, I would expect to turn the blend pot and and it would behave like a volume pot, if the fault was after IC1a. The shorted IC could also seriously drag the rail (VCC) down causing a distorted output but at a much lower volume.

If I had to take a stab in the dark, I'd be looking at the 4047 IC, but as we said earlier never assume anything.

I did try and post photo's, it didn't work out for me.

Yours Sincerely

Mark Abbott

[bassman]

I bought a stereo memory man off of ebay that didn't work - after checking the mechanicals I reseated the ics and that was all it needed.  That was a well-spent $35!

bassman

[squidsquad]

I had one die once. 
Luckily it was easy to spot...a burn mark on a big cap. 
Replaced it...got her working.

Another one had a beer dumped on it...never recovered...hehe!

[Mark Abbott]

I'm going to try and find time to have a crack at it tonight. I have had a few more thoughts about it, I'll keep posting the findings and hopefully the fix. The Howard Davis Leslie mod does sound quite tempting though.

Yours Sincerely

Mark Abbott