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64 Gretsch 6120, 65 Fender Tremolux and a 58 Supro 1624T
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Discussion Starter #1
I'll pay for the repairs obviously... pedal gets power and signal passes though when bypassed. However when engaged no signal passes at all. LED does light up though so it's getting power. The only visible damage inside is a crispy resistor.

received_10160495562715553.jpeg
 

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Anny local electronics repair guy can help you out. I'd be willing to bet just that one resistor is the issue; had something similar with a Big Muff when a bud plugged the wrong power supply into it. Figuring out what value that resistor was might be the hardest part

Apparently these are an Electric Mistress clone, and here's the schem for that: http://www.metzgerralf.de/elekt/stomp/mistress/images/deluxe-electric-mistress-v5-schematic.gif . That part is too small to be the 2W resistor right off the power in, and "R2" makes me think it's first or second off the input jack. Any electronics person would be able to look at the board traces and parts around it and figure it out. I'd do it but it's not worth the shipping. Find an old local dude who used to fix TVs.

Hmmm... I can see 2 identical resistors in series after it, but can't find that on the schem (could be a heavily modified copy or that could be internet misinformation... or I am not seeing the right colours in the pic - looks like Red, black, black, orange, brown - 200k or 130R depending which way you read it - 130R is a bit weird so ...). Your best bet for finding the original value is asking other owners to read off the color bands to you (or even better, measure it). Hartman is no longer in Biz I think.
 

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64 Gretsch 6120, 65 Fender Tremolux and a 58 Supro 1624T
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Discussion Starter #4
Anny local electronics repair guy can help you out. I'd be willing to bet just that one resistor is the issue; had something similar with a Big Muff when a bud plugged the wrong power supply into it. Figuring out what value that resistor was might be the hardest part

Apparently these are an Electric Mistress clone, and here's the schem for that: http://www.metzgerralf.de/elekt/stomp/mistress/images/deluxe-electric-mistress-v5-schematic.gif . That part is too small to be the 2W resistor right off the power in, and "R2" makes me think it's first or second off the input jack. Any electronics person would be able to look at the board traces and parts around it and figure it out. I'd do it but it's not worth the shipping. Find an old local dude who used to fix TVs.

Hmmm... I can see 2 identical resistors in series after it, but can't find that on the schem (could be a heavily modified copy or that could be internet misinformation... or I am not seeing the right colours in the pic - looks like Red, black, black, orange, brown - 200k or 130R depending which way you read it - 130R is a bit weird so ...). Your best bet for finding the original value is asking other owners to read off the color bands to you (or even better, measure it). Hartman is no longer in Biz I think.
Found my answer. .. kinda. It's a common problem I guess. I sent Brian a message to see if he can help.

https://guitarscanada.com/index.php?threads/looking-to-have-a-hartman-flanger-repaired-fixed-by-bduguay.80680/page-2
 

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If my management allows me to squeeze in some time, I can take a look at it when I'm out your way at the end of the month. If memory serves, the Hartman is basically an Electric Mistress, adapted to use an MN3007 delay chip instead of the original SAD1024?

The part numbering of the Hartman won't necessarily correspond to the part numbering of any of the EM issues. The "crispy" resistor is R2. Could you possibly tell me what other components each end of that resistor connects to, and what thgeir values are. Conceivably that would identify what segment of the overall circuit it is situated in, and from there, what possibly went wrong.

I've found some gutshots of the Hartman on-line, but the resolution doesn't really allow me to see what the value is clearly.

HOWEVER, you'll find this post interesting, since the person has the same problem as you: R1 Resistor value for Hartman Flanger.



In which case, it is quite possible that R2 is part of the power supply, and is 10 ohms. Certainly looks like it from this picture. I must have about 20 or more different schematics for the EM, with a variety of power-supply circuits. But several of them show a 10 ohm I can bring you a bunch of 10 ohm resistors to sub.
 

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Have you always used the same power supply? Was it working fine then suddenly not?
B.
I'll pay for the repairs obviously... pedal gets power and signal passes though when bypassed. However when engaged no signal passes at all. LED does light up though so it's getting power. The only visible damage inside is a crispy resistor.

View attachment 205057
 

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64 Gretsch 6120, 65 Fender Tremolux and a 58 Supro 1624T
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Discussion Starter #8
Have you always used the same power supply? Was it working fine then suddenly not?
B.
Not sure on the history of the pedal, it was gifted to me in it's current condition. From what I have found after referring to the google machine is that more than one person have had the same problem with the same resistor.
 

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Worse comes to worse, my kid is coming back home for a visit once the grad ceremony is over and returning to Halifax after a brief visit home. I can pick it up from you, bring it back home where I can give it a more in-depth look, hopefully fix it, and send it back with him when he returns to your area.

It's an open offer. No pressure.
 

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64 Gretsch 6120, 65 Fender Tremolux and a 58 Supro 1624T
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Discussion Starter #10
Worse comes to worse, my kid is coming back home for a visit once the grad ceremony is over and returning to Halifax after a brief visit home. I can pick it up from you, bring it back home where I can give it a more in-depth look, hopefully fix it, and send it back with him when he returns to your area.

It's an open offer. No pressure.
PM Sent!
 

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This reminds me of what Joe Peschi's character says in the movie Goodfellows after they blow a guys brains out in the car... His henchmen are high fiving...

Don't start sucking each others ****'s, just yet...we still have to clean up the mess.

Could be one resistor...or all the IC's...
 

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Where is the MN3007 in that pic? I've always been curious what Hartman used for bbds... apparently there were at least two versions produced over the years.
 

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Well, that was an easy one. I thought there'd be some detective work involved, but none was needed. The Hartman board has all the component values legended on the board under the component. So, remove the burnt resistor, clean the gunk away with a Q-tip, and as expected it said "10R" underneath. Subbed a new 1/2W unit for the burnt 1/4W there, and we got flanging on fire-up.

As I told Chitmo/Fred, not really my kind of flanger, but certainly gets you instant Andy Summers. Decently made pedal. Neat wiring. The enclosure in Chinese-made with an oddball screw thread, quite unlike what Hammond uses.
 
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