73-75 Serge panels from Zthee

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gigasturtz
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Post by gigasturtz » Sat Dec 29, 2018 12:49 am

thinking about building one of these. has anybody built one into a suitcase?

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chorus7
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Post by chorus7 » Mon Dec 31, 2018 8:04 am

Can anyone recommend a place in Canada or the States to get a reverb tank for the 73-75? Does anyone have any recommendations as far as parts number?

Also where could I find boats for the two panels?

Many thanks...

Jonny
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Post by Jonny » Mon Dec 31, 2018 9:15 am

I'm assembling the parts and found the reverb at this place:

https://amprepairparts.com/reverb.htm?f ... rEIHNhgA#9

You can use Hammond 1773 boats (which I plan on using) or something from Bud Industries.

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chorus7
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Post by chorus7 » Mon Dec 31, 2018 4:05 pm

Jonny

Many thanks :hail:

Is there a difference between the Hammond and bud boats?

Jonny
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Post by Jonny » Tue Jan 01, 2019 10:26 pm

New to Serge DIY, but from what I can gather, they are pretty similar, AC-423 seems to be the part number.

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luchog
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Post by luchog » Tue Jan 08, 2019 3:43 pm

Doesn't look like anyone mentioned this, but the Website says the DIY "Homebuilt" kits are back in stock!

"Back in stock and will ship first week in January 2019"

https://shop.73-75.com/diy-system

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chorus7
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Post by chorus7 » Fri Jan 11, 2019 7:01 am

I got one of these systems from a friend who had it built by Jon Peters... It unfortunately still needs some work...

I plugged in the VCO just to test it but all I get is really high pitches? Even when I turn the knobs it’s only slightly lower... Am I missing something with the Serge VCO? How should it be patched to test the audio?

Many thanks...

ashleym
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Post by ashleym » Fri Jan 11, 2019 9:48 am

chorus7 wrote:I got one of these systems from a friend who had it built by Jon Peters... It unfortunately still needs some work...

I plugged in the VCO just to test it but all I get is really high pitches? Even when I turn the knobs it’s only slightly lower... Am I missing something with the Serge VCO? How should it be patched to test the audio?

Many thanks...
Each module is “independent “ and you should get the full (ok without modulation) range from the panel controls.

ashleym
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Post by ashleym » Fri Jan 11, 2019 9:51 am

luchog wrote:Doesn't look like anyone mentioned this, but the Website says the DIY "Homebuilt" kits are back in stock!

"Back in stock and will ship first week in January 2019"

https://shop.73-75.com/diy-system
But no news on the other panels becoming available.........

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luchog
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Post by luchog » Thu Jan 17, 2019 7:23 pm

ashleym wrote:
luchog wrote:Doesn't look like anyone mentioned this, but the Website says the DIY "Homebuilt" kits are back in stock!

"Back in stock and will ship first week in January 2019"

https://shop.73-75.com/diy-system
But no news on the other panels becoming available.........
I'm really hoping they'll be available as DIY as well, rather than only as completed units.

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diophantine
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Post by diophantine » Mon Feb 11, 2019 9:07 pm

Has anyone installed LEDs on the comparator outputs?

The middle LED (if placed in the lower left hand corner of the output box) would be right over the LM3900, so I'm a tad concerned about clearance as I'll be socketing my ICs. (So only ~3mm clearance - would have to be picky with lenses.)

resynthesize
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Post by resynthesize » Sun Feb 17, 2019 12:56 pm

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Jonny
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Post by Jonny » Tue Feb 19, 2019 9:36 pm

Seeking some help with troubleshooting the power supply. I checked the power supply and it is +24v into the board. The readings: for +12v, getting 7.4-7.5 with trimmer, for +6v, getting +13.6v (trimmer doesn't seem to adjust much), and for -12v, getting -4.5v. I did have to redo the regulators due to height, but they seem to be right (LM317's on the +12 and +6 and LM 337 on the -12v). It's also odd that the 3 trimmers don't seem to give me much range if any. Tried resoldering them too. Thanks in advance to anybody who can advise what to do or try!

Image

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cygmu
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Post by cygmu » Wed Feb 20, 2019 2:40 am

That's odd... Double check all the resistor values and the trimmer values. I can't really read them from the photos. You need 1k5 fixed / 500R trimmer / 220 R fixed in the +/- 12V sections and 470R fixed / 500R trimmer / 220 R fixed in the 6V section.

It sort of looks like you have some red-red-yellow resistors in there which would be 220k . If those are the ones that should be 220 Ohm, that might be the answer. But, I am not convinced I have read the photograph correctly, so just have a look!

EDIT: I think I saw a better photo of the same build on Facebook where the resistors are definitely red-red-yellow which is definitely wrong!

Jonny
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Post by Jonny » Wed Feb 20, 2019 8:29 am

Yes, that's the issue. :doh: Thanks for the help!

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ishi
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Post by ishi » Mon Apr 01, 2019 3:42 pm

Don't know if the news spread already to other threads, but Jon is freelancing again & working on projects, including the rest of the 73-75 modules.. Also sold some of the 73-75 prototypes (Voice & Control!) to fund his future activities.

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diophantine
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Post by diophantine » Mon Apr 01, 2019 4:14 pm

ishi wrote:Don't know if the news spread already to other threads, but Jon is freelancing again & working on projects, including the rest of the 73-75 modules.. Also sold some of the 73-75 prototypes (Voice & Control!) to fund his future activities.
Unfortunately it sounds like they're all pre-assembled and not DIY. Obviously that's how they were originally advertised, but I (and others) were hoping that with the success (or at least popularity) of the Homebuilt panels any new ones would also be available as DIY.

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ishi
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Post by ishi » Mon Apr 01, 2019 6:03 pm

Oh, that's not how I interpreted it:

"He's working on several projects, one of them being the series production of the rest of the 73-75 modules! .. To fund the initial manufacturing run he is selling some of his prototypes .."

i was assuming that he's selling built prototypes to fund manufacturing of panels & pcb's. You might be right, hope not :) Well, we'll have to wait and see.

ashleym
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Post by ashleym » Tue Apr 02, 2019 12:59 pm

Perhaps he could do some runs of Voice, Control and Preset panels and boards? This would help fund some built versions. I base this on the Homebuilt having sold OK numbers.

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ishi
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Post by ishi » Wed Apr 03, 2019 3:29 am

ashleym wrote:Perhaps he could do some runs of Voice, Control and Preset panels and boards? This would help fund some built versions. I base this on the Homebuilt having sold OK numbers.
I've asked that same question. Waiting for an answer...

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diophantine
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Post by diophantine » Tue Apr 09, 2019 8:00 pm

What sort of range are people getting on the Negative Slew?

I intended to calibrate mine the original way, with the max frequency at 1kHz on the top one. But, it maxed out at around 900Hz. And that that frequency, the min frequency was around 6Hz - waaay too high for me.

Now I have them both calibrated to 500Hz max, which gives a min period of around 7-8 seconds.

Is that similar to what others have?

Skilling
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Post by Skilling » Fri May 10, 2019 2:50 am

EDIT: Got answers in the FB group. They work. :)
-----------------------

Sorry if this question has come up earlier in the thread, but would these knobs from Thonk work for the DIY panels?

https://www.thonk.co.uk/shop/alpha-9mm- ... tical-t18/

Skilling
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Post by Skilling » Thu Jun 06, 2019 1:47 pm

I struggle to understand the trim instructions for the Gate module. I have fiddled with the trim pots and have something that might work at he moment, but it's a little bit so-so. I also find that trimpot 3 have very little affect, but I'm not sure what to look for.
I would be super grateful if someone could explain the said trimming routine step by step. :help:

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GrantB
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Post by GrantB » Thu Jun 06, 2019 1:52 pm

Skilling wrote:I struggle to understand the trim instructions for the Gate module. I have fiddled with the trim pots and have something that might work at he moment, but it's a little bit so-so. I also find that trimpot 3 have very little affect, but I'm not sure what to look for.
I would be super grateful if someone could explain the said trimming routine step by step. :help:
I found this page useful for calibrating my R6 Gates:

https://modularsynthesis.com/serge/box1/serge1.htm

Skilling
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Post by Skilling » Thu Jun 06, 2019 1:56 pm

GrantB wrote:
Skilling wrote:I struggle to understand the trim instructions for the Gate module. I have fiddled with the trim pots and have something that might work at he moment, but it's a little bit so-so. I also find that trimpot 3 have very little affect, but I'm not sure what to look for.
I would be super grateful if someone could explain the said trimming routine step by step. :help:
I found this page useful for calibrating my R6 Gates:

https://modularsynthesis.com/serge/box1/serge1.htm

Oh, thanks!!! :bananaguitar: I'll check it out!

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