ARP 1601 clone Build Thread

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gorlandi1972
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Re: ARP 1601 clone Build Thread

Post by gorlandi1972 » Sun Apr 05, 2020 7:00 pm

Anyone know is R13 supposed to be 10K or 1M? description says 10k mouser # is 1M?

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Kipling
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Re: ARP 1601 clone Build Thread

Post by Kipling » Mon Apr 06, 2020 2:24 am

gorlandi1972 wrote:
Sun Apr 05, 2020 7:00 pm
Anyone know is R13 supposed to be 10K or 1M? description says 10k mouser # is 1M?
R13 is 10k.

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TheDegenerateElite
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Re: ARP 1601 clone Build Thread

Post by TheDegenerateElite » Wed Apr 08, 2020 2:16 am

Reflow the solder on all three of the SMT chips, if they are in your build, making sure that the joints are solid and not shorted.

I fixed an intermittent clock issue on my build by doing this.

checkit
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Re: ARP 1601 clone Build Thread

Post by checkit » Wed Apr 08, 2020 5:04 am

Thanks a lot for the hint. I will try to do this.

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Jim the Oldbie
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Re: ARP 1601 clone Build Thread

Post by Jim the Oldbie » Thu Apr 09, 2020 12:02 am

"It's alive - ALIIIVE!!!"

Image

(Sorry, heh.) :party:

By the way: THANK YOU THANK YOU and finally THANK YOU to everyone involved in making this kit happen!!

Side note: Apparently the Model D isn't very happy with the 10V gate inputs from this thing - whole lotta thumpin' goin' on!

[EDIT] Oops, more like 14V, yeesh. Gonna need an old-to-new school attenuator methinks.
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Last edited by Jim the Oldbie on Thu Apr 09, 2020 8:18 am, edited 7 times in total.

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Re: ARP 1601 clone Build Thread

Post by Jim the Oldbie » Thu Apr 09, 2020 12:33 am

Has anyone messed with adding a forward/reverse mod, using a bidirectional counter? If not, I may have a look.

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Kipling
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Re: ARP 1601 clone Build Thread

Post by Kipling » Sat Apr 11, 2020 3:58 am

Jim the Oldbie wrote:
Thu Apr 09, 2020 12:02 am
"It's alive - ALIIIVE!!!"

(Sorry, heh.) :party:

By the way: THANK YOU THANK YOU and finally THANK YOU to everyone involved in making this kit happen!!

Side note: Apparently the Model D isn't very happy with the 10V gate inputs from this thing - whole lotta thumpin' goin' on!

[EDIT] Oops, more like 14V, yeesh. Gonna need an old-to-new school attenuator methinks.
Excellent news, and you're most welcome.

To reduce the gate, clock & position 1 out voltages to make it more suitable for non-ARP gear, you could build a series resistor (try 22k or higher) and 5V clamping zener diode between tip and sleeve (ground) into a 3.5mm jack plug at the Moog end of each cable. Make sure you label up any special leads and always use them the right way round to avoid damaging the output transistors on the sequencer. Either that or build 6 of these attenuators into a small project box with 14V in and 5V out jack sockets accordingly.

Attenuator.JPG

For the forthcoming Rev 6a, I have included trimmers for each of these outputs on the main PCB so you can set them to whatever voltage your equipment prefers.

I have not considered a reversible counter. Could be interesting!
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KSS
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Re: ARP 1601 clone Build Thread

Post by KSS » Sat Apr 11, 2020 5:46 am

Jim the Oldbie wrote:
Thu Apr 09, 2020 12:33 am
Has anyone messed with adding a forward/reverse mod, using a bidirectional counter? If not, I may have a look.
Yes, it's been done. Can't say more. Commercial product supposed to have been released at Spring shows until pandemic changed everyone's plans.

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Jim the Oldbie
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Re: ARP 1601 clone Build Thread

Post by Jim the Oldbie » Sat Apr 11, 2020 6:23 am

Thanks for the heads-up on this. I'll keep an ear to the rail.

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Re: ARP 1601 clone Build Thread

Post by Jim the Oldbie » Sat Apr 11, 2020 6:35 am

Kipling wrote:
Sat Apr 11, 2020 3:58 am
To reduce the gate, clock & position 1 out voltages to make it more suitable for non-ARP gear, you could build a series resistor (try 22k or higher) and 5V clamping zener diode between tip and sleeve (ground) into a 3.5mm jack plug at the Moog end of each cable. Make sure you label up any special leads and always use them the right way round to avoid damaging the output transistors on the sequencer. Either that or build 6 of these attenuators into a small project box with 14V in and 5V out jack sockets accordingly.

[Attenuator.JPG]
Thanks for posting this, you saved me some time. I'll definitely build a couple of these for the short term, since the 1601 and Model D are a surprisingly fun matchup, for this old fart at least.

I'm about to build up a small Euro case with some oddball stuff, including a bunch of attenuverter/mixers etc. to help with translation to & from all the different old stuff lying about. Looking forward to getting everything conversational.

gorlandi1972
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Re: ARP 1601 clone Build Thread

Post by gorlandi1972 » Sun Apr 12, 2020 12:15 am

Can anyone confirm what value C9 should be?

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Kipling
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Re: ARP 1601 clone Build Thread

Post by Kipling » Sun Apr 12, 2020 2:55 am

gorlandi1972 wrote:
Sun Apr 12, 2020 12:15 am
Can anyone confirm what value C9 should be?
C9 is 20nF (22nF is close-enough).

If you open the PDF of the board layout on post #0 (ARP 1601 Sequencer Rev 4 - PCB (full).pdf) each component has a hot-spot you can click on to view its attributes/value.

Hope this helps.

gorlandi1972
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Re: ARP 1601 clone Build Thread

Post by gorlandi1972 » Sun Apr 12, 2020 8:22 am

Thanks appreciate the help..

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Re: ARP 1601 clone Build Thread

Post by synthcube » Mon Apr 13, 2020 1:08 pm

quick update--- v6a pcbs are in and look really nice. Much thanks (AGAIN) to Kipling for the awesome work towards this DIY project. We will be revising our BOM accordingly. Next batch of panels and boats are expected here around 5/1/2020
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Kipling
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Re: ARP 1601 clone Build Thread

Post by Kipling » Mon Apr 13, 2020 1:53 pm

:tu:

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synthcube
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Re: ARP 1601 clone Build Thread

Post by synthcube » Tue Apr 14, 2020 2:57 pm

updated synthube kit bom-- for V6a PCbs
1601 Seq rev6a synthCube Kit BOM.pdf
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Re: ARP 1601 clone Build Thread

Post by spacecadet » Mon Apr 20, 2020 5:16 pm

Jim the Oldbie wrote:
Thu Apr 09, 2020 12:33 am
Has anyone messed with adding a forward/reverse mod, using a bidirectional counter? If not, I may have a look.

Z7 - is a CD4520 that contains the counter. Its dual counter, so counter A is used for the main sequencer, and counter B is used for the randomizer.

http://www.ti.com/lit/ds/symlink/cd4520b-mil.pdf

So there is no drop in replacement chip that has this up/down functionality, and you have the complication to maintain the operation of counter b for the randomizer.

There is this chip that can go in either direction and is also a 4 bit counter. The presettable functionality could be left unused/tied.

http://www.ti.com/lit/ds/symlink/cd4516b-mil.pdf

Its not pin compatible, so you would have to design/build a daughter card that fits into Z7's socket and has both the CD4520 and CD4516 on it - if you don't want to hack the main PCB

Then possibly some additional glue logic depending on how/when you want the up/down control to function.

You could of course go back to basics and design a counter from scratch using discrete logic and Karnough maps :hihi:

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Re: ARP 1601 clone Build Thread

Post by PPE » Wed Apr 22, 2020 10:50 pm

Hey all. Will the trimmers for the gate outputs be accessible from the front panel?

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Kipling
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Re: ARP 1601 clone Build Thread

Post by Kipling » Thu Apr 23, 2020 1:58 am

PPE wrote:
Wed Apr 22, 2020 10:50 pm
Hey all. Will the trimmers for the gate outputs be accessible from the front panel?
Unfortunately not as designed, though you could drill the rear of the boat to suit as I’ve specified it for side-adjust trimmers. That could be a little fiddly trying to engage with the trimmer as they’ll be about 20mm in from the rear face so I’d recommend using a plastic screwdriver to avoid shorting anything.

Another option wold be to use normal top-adjust trimmers (3362P) and mount them on the front panel side of the PCB and then drill the front panel accordingly.

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Re: ARP 1601 clone Build Thread

Post by PPE » Thu Apr 23, 2020 8:42 am

Kipling wrote:
Thu Apr 23, 2020 1:58 am
PPE wrote:
Wed Apr 22, 2020 10:50 pm
Hey all. Will the trimmers for the gate outputs be accessible from the front panel?
Unfortunately not as designed, though you could drill the rear of the boat to suit as I’ve specified it for side-adjust trimmers. That could be a little fiddly trying to engage with the trimmer as they’ll be about 20mm in from the rear face so I’d recommend using a plastic screwdriver to avoid shorting anything.

Another option wold be to use normal top-adjust trimmers (3362P) and mount them on the front panel side of the PCB and then drill the front panel accordingly.
Thanks for the tips Kipling! Could be cool to make these accessible from the outside in future builds.
Last edited by PPE on Thu Apr 23, 2020 11:52 am, edited 1 time in total.

jandavidhoo
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Re: ARP 1601 clone Build Thread

Post by jandavidhoo » Thu Apr 23, 2020 10:05 am

Will I be able to order a pcb + panel at synthcube or is the new run already sold out?

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Kipling
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Re: ARP 1601 clone Build Thread

Post by Kipling » Thu Apr 23, 2020 1:24 pm

jandavidhoo wrote:
Thu Apr 23, 2020 10:05 am
Will I be able to order a pcb + panel at synthcube or is the new run already sold out?
I believe they have the PCBs but are waiting on a delivery of panels, boats etc.

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Re: ARP 1601 clone Build Thread

Post by Kipling » Thu Apr 23, 2020 1:38 pm

PPE wrote:
Thu Apr 23, 2020 8:42 am

Thanks for the tips Kipling! Could be cool to make these accessible from the outside in future builds.
Yes maybe, but I'd need to tidy up the PCB a bit first to put the trimmers closer to the outputs they control, as presently they're not all ideally placed for that.

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Re: ARP 1601 clone Build Thread

Post by musicorchard » Thu Apr 23, 2020 2:52 pm

Thanks Kipling for your revisions on this! Question that I hope wasn't answered already... I have the Rev. 5 board, but I really want the additional trim pots. Is there a way to add them to the existing board either with jumper wires or a spare PCB board? Maybe that way I could still use the current revision and also have the ability to have an opening in the rear panel to adjust the trim pots.

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Re: ARP 1601 clone Build Thread

Post by PPE » Thu Apr 23, 2020 7:17 pm

musicorchard wrote:
Thu Apr 23, 2020 2:52 pm
Thanks Kipling for your revisions on this! Question that I hope wasn't answered already... I have the Rev. 5 board, but I really want the additional trim pots. Is there a way to add them to the existing board either with jumper wires or a spare PCB board? Maybe that way I could still use the current revision and also have the ability to have an opening in the rear panel to adjust the trim pots.
I would very much be into this mod as well. I have a JHulk 1601... I think it's Rev 3. Thanks kipling!

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