Search found 13 matches

by Fuzzlefty77
30 Jul 2020, 14:59
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

WORKING! :D After fixing the glaring Collector to ground mistake on the 2N5087. Still nowt....... Then here comes the really dumb mistake (no the above wasn't the worst), I'd soldered the 12k resistor in the wrong place :oops: I'd skipped across a position so no wonder it didn't do much: Doh.jpg But...
by Fuzzlefty77
29 Jul 2020, 15:51
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Scruffie wrote:
29 Jul 2020, 15:28
Well seeing as the 2N5087 collector should be grounded, I'd say there's still a mistake :)
:oops: :lol: Jeez, thats so glaringly obvious. Doh!
by Fuzzlefty77
29 Jul 2020, 13:43
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Would help if I actually had said what the voltages at the 2N5087 were:

C = 9v
B = 8.5V
E = 4.25V

Any advice if these are what should be expected?
by Fuzzlefty77
29 Jul 2020, 09:03
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

The saga continues....... I've double checked my conversion and everything seems good to the schematic The 2N5087 reads good, I get 0.725v across E(+) to B (-) and C(+) to B(-) and o/l in every other scenario. Do i need to check it in any other way? I have now managed to get 4v coming in at Pin 3 on...
by Fuzzlefty77
24 Jul 2020, 17:13
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Scruffie wrote:
24 Jul 2020, 14:19
The bias :)

Pin 3 is the input, its voltage is adjusted by the bias trim, the output pins 7 & 8 track the input voltage.
Unfortunately the 2.3v on Pin 3 is with the bias maxed. :shock:
by Fuzzlefty77
24 Jul 2020, 13:45
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Got hold of a "good" MN3007 and got these results to compare with Scruffies recommended results: 1. 8.5 - spot on 2. 4.25 - spot on 3. 2.3 - down on what is expected. 4. 0 - spot on 5. 0 - spot on 6. 4.25 - spot on 7. 2.6 - down on what is expected 8. 2.6 - down on what is expected So my voltages IN...
by Fuzzlefty77
19 Jul 2020, 14:40
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

I did the schoolboy error of buying some off eBay.
Any good sources currently in the UK for MN3007?
by Fuzzlefty77
19 Jul 2020, 13:04
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Sooooo.......first thing, I re-checked all pins previously on all Op Amps and I go a more positive result from the LM358. Previous voltages read in () 1 - 6.8 ( 1.8 ) 2 - 6.8 ( 4.1 ) 3 - 4.9 ( 4.1 ) 4 - GRD 5 - 7.3 ( 2.2 ) 6 - 4.9 ( 2.2 ) 7 - 4.9 ( 4.1 ) 8 - 9.1 ( 9.1 ) I noticed on the board there ...
by Fuzzlefty77
17 Jul 2020, 19:05
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

What are the voltages on the MN3007? Going from your previous voltages, you should expect to see something in the region of. 1. 8.5 2. 4.25 3. 4 4. 0 5. 0 6. 4.25 7. 4.5 8. 4.5 A BBD requires the correct power supply voltages, a correct input bias voltage, anti-phase clock signals and a source foll...
by Fuzzlefty77
17 Jul 2020, 13:09
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

So......interestingly (or maybe not) I converted this to an MN3007 schematic and it made zero change!!

Still no chorus effect. Maybe the SAD1024 wasn't dead after all and there is another issue?! :roll:
by Fuzzlefty77
10 Jul 2020, 13:32
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

You are everywhere it seems lol. Should we just continue on here? Which comes back to the SAD, bias voltage on its input, 0.3V above ground on its output. You can redo the solder joints, clean the socket, check the 39k output resistor coming from pins 6 & 11 isn't a short and lift one leg of the 10...
by Fuzzlefty77
10 Jul 2020, 09:22
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Yeah sorry Scruffie, I only posted here and on the EHX forums with this issue. You are everywhere it seems lol. Should we just continue on here? Just to clarify what I've just posted on the EHX forum (doh): Output voltage on SAD changes a tiny bit to 0.3v when input bias is adjusted to max (6.75v). ...
by Fuzzlefty77
09 Jul 2020, 15:02
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 21
Views: 1061

Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Hi guys, Apologies for my first post being a bit of a long winded cry for help but I’ve picked up a non functioning EHX Small Clone. To my delight it was a vintage one from the 80’s with the SAD1024 chip and all seems totally original. I still can’t seem to get it working after performing the follow...