ARP 1601 clone Build Thread

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Altitude909
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Post by Altitude909 » Tue Aug 11, 2015 6:35 am

I'm sorted. Unsurprisingly, everything works fine once you put the parts where they are supposed to go :razz:

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Post by finnurbjarna » Tue Aug 11, 2015 3:28 pm

I'm happy to say that the 1Nf cap on the Step switch seems to have stopped it's erratic behaviour completely - (thanks,
John).

Following elmegil's advice I put a couple of coats of spray paint on the panel and am hoping that it will preserve the legend well into the 22nd century and beyond. It actually gives the panel a rather lovely finish. This is what I used (less than a tenner from Homebase here in the UK):

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Broadwave
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Post by Broadwave » Wed Aug 12, 2015 3:04 am

Hmmm, Not sure what's going on - Sequencer now completed and everything works fine... except that if I stop the sequence and press RESET (LED slider 1 lit) when I restart the sequence, step 1 doesn't sound... i.e. gate outputs start at step 2.

Strange, I'll have a poke around and try to figure it out.

EDIT:

Well, I can't find anything wrong... but I found this demo of a genuine ARP 1601, and it appears that step 1 is indeed ignored when the sequence is stopped, reset and started (@ 13 seconds in). Watch carefully and you'll see the sequence does actually start on step 2 :hmm:

Can any of you kind folks confirm this for me - I'm pulling out what's left of my hair.
Last edited by Broadwave on Wed Aug 12, 2015 10:48 pm, edited 1 time in total.

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nickster
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Post by nickster » Wed Aug 12, 2015 7:30 am

[quote="finnurbjarna"]I'm happy to say that the 1Nf cap on the Step switch seems to have stopped it's erratic behaviour completely - (thanks,
John).

Following elmegil's advice I put a couple of coats of spray paint on the panel and am hoping that it will preserve the legend well into the 22nd century and beyond. It actually gives the panel a rather lovely finish. This is what I used (less than a tenner from Homebase here in the UK):

Interested to see a picture of your sprayed faceplate, if possible. Thinking of following your lead but want to be sure it looks the way I'd like. Thanks in advance.

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MrRoper
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Post by MrRoper » Wed Aug 12, 2015 10:03 am

Hi gents, had loads of fun putting this together this week, was just about to fire her up and realized I don't have a Power supply for it :bang: ....

I remember now that Mouser wouldn't ship the one on the BOM to the UK so do any UK based wigglers have a suggestion for an alternative?

As always thanks so much for any help!

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Post by finnurbjarna » Wed Aug 12, 2015 12:50 pm

MrRoper wrote:Hi gents, had loads of fun putting this together this week, was just about to fire her up and realized I don't have a Power supply for it :bang: ....

I remember now that Mouser wouldn't ship the one on the BOM to the UK so do any UK based wigglers have a suggestion for an alternative?

As always thanks so much for any help!
I went the cheap route and am just using this:

http://www.frequencycentral.co.uk/?page_id=894

with this:

http://cpc.farnell.com/stontronics/s223 ... 0000010070

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Broadwave
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Post by Broadwave » Wed Aug 12, 2015 1:21 pm

MrRoper wrote: I remember now that Mouser wouldn't ship the one on the BOM to the UK so do any UK based wigglers have a suggestion for an alternative?
I got mine from CPC/Farnell £14.73, free postage :wink:

I also bought a matching DC socket 2.1mm x 5.5mm, just to be on the safe side (although I *think* the mouser one is ok).
Last edited by Broadwave on Wed Aug 12, 2015 10:06 pm, edited 1 time in total.

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MrRoper
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Post by MrRoper » Wed Aug 12, 2015 4:23 pm

Thanks for the replies guys. Broadwave, do you have a link to the one you got from Farnell?

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Kipling
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Post by Kipling » Wed Aug 12, 2015 4:30 pm

MrRoper wrote:Thanks for the replies guys. Broadwave, do you have a link to the one you got from Farnell?
There is an embedded link in the CPC/Farnell text in his post

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Post by finnurbjarna » Thu Aug 13, 2015 5:32 am

nickster wrote:Interested to see a picture of your sprayed faceplate, if possible. Thinking of following your lead but want to be sure it looks the way I'd like. Thanks in advance.
Here are a couple of pictures. There are a few little blemishes in the varnish, probably because I sprayed my panel in the back garden; there was a light breeze so a few bits of dust etc got lodged in the wet paint. A more controlled environment would no doubt yield more perfect results (I was impatient and worried about the disappearing lettering :hyper: )

Image

Image

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efexor
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Post by efexor » Thu Aug 13, 2015 6:15 am

Very nice.
As a carpenter i will built something similar as a alu boat is way to expensive to have only 1 built.

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MrRoper
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Post by MrRoper » Thu Aug 13, 2015 7:08 am

Kipling wrote:
MrRoper wrote:Thanks for the replies guys. Broadwave, do you have a link to the one you got from Farnell?
There is an embedded link in the CPC/Farnell text in his post
Hahaha nice one, my old eyes couldn't see it! :tu:

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elmegil
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Post by elmegil » Thu Aug 13, 2015 10:00 am

MrRoper wrote:
Kipling wrote:
MrRoper wrote:Thanks for the replies guys. Broadwave, do you have a link to the one you got from Farnell?
There is an embedded link in the CPC/Farnell text in his post
Hahaha nice one, my old eyes couldn't see it! :tu:
The forum settings don't do a decent job of making it clear, I don't think it's your old eyes.

I have gotten in the habit of mousing around whenever someone posts something like that just to see, because it does change the link when you mouse over it....

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Post by finnurbjarna » Fri Aug 14, 2015 4:22 am

Broadwave wrote:Hmmm, Not sure what's going on - Sequencer now completed and everything works fine... except that if I stop the sequence and press RESET (LED slider 1 lit) when I restart the sequence, step 1 doesn't sound... i.e. gate outputs start at step 2.

Strange, I'll have a poke around and try to figure it out.

EDIT:

Well, I can't find anything wrong... but I found this demo of a genuine ARP 1601, and it appears that step 1 is indeed ignored when the sequence is stopped, reset and started (@ 13 seconds in). Watch carefully and you'll see the sequence does actually start on step 2 :hmm:

Can any of you kind folks confirm this for me - I'm pulling out what's left of my hair.
I asked this question a few posts back and can confirm that my unit is the same:

Reset does not re-trigger step 1 from 'Clock Out', 'Clocked Gate 1 Out' or 'Gate Bus 2'. HOWEVER: it does re-trigger Step 1 from 'Gate Busses 1 & 3' as well as from 'Position 1 Out'. :hmm:

Mine is also that same in terms of starting up the sequencer when powered up, which I think you mentioned in the ordering thread.


EDIT: Upon further investigation, Step 1 is only re-triggered on any of the Gate Busses 1-3 if the previous step is DIFFERENT to the relevant Gate Bus. For example, Gate Bus 1 will only be re-triggered on step one if the the current (illuminated) sequencer step is switched to Gate Bus 2 or 3, etc.

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Broadwave
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Post by Broadwave » Fri Aug 14, 2015 6:11 am

finnurbjarna wrote: Mine is also that same in terms of starting up the sequencer when powered up, which I think you mentioned in the ordering thread.


EDIT: Upon further investigation, Step 1 is only re-triggered on any of the Gate Busses 1-3 if the previous step is DIFFERENT to the relevant Gate Bus. For example, Gate Bus 1 will only be re-triggered on step one if the the current (illuminated) sequencer step is switched to Gate Bus 2 or 3, etc.
I've just had it confirmed by an owner of an original 1601 - this behavior is perfectly normal... I can breathe a sigh of relief :yay:

Thanks finnurbjarna.

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Post by nickster » Fri Aug 14, 2015 6:25 am

...Here are a couple of pictures. There are a few little blemishes in the varnish, probably because I sprayed my panel in the back garden; there was a light breeze so a few bits of dust etc got lodged in the wet paint. A more controlled environment would no doubt yield more perfect results (I was impatient and worried about the disappearing lettering :hyper: )...

Thanks very much for this. Your case looks lovely! Can't see any blemishes either. Nice job!

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Altitude909
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Post by Altitude909 » Fri Aug 14, 2015 7:03 am

Broadwave wrote:..

I've just had it confirmed by an owner of an original 1601 - this behavior is perfectly normal... I can breathe a sigh of relief :yay:

Thanks finnurbjarna.
Mine has the same behavior as well

It seems that only the steps reset, not the clock so if you tap it when the clock pulse is high, it will start on the subsequent step. It's easier to see when you slow the clock way down.

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Post by finnurbjarna » Sat Aug 15, 2015 4:08 am

I'm glad it all works as it should and that these idiosyncrasies are from the original design.

Thanks for your kind words about the case. I botched it together from a left-over piece of oak. Having the plans for the boat makes it all much easier, so thanks again @satindas for those.

I'm having lots of fun with the sequencer - feel like I lucked out getting on board with this project!

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Post by finnurbjarna » Sat Aug 15, 2015 10:36 am

I spoke too soon - I do have a problem:

When set to 8/2 I'm not getting a separate sequence out of Quantized Output B, only the same as out of Quantized Output A ...

I am, however, getting a separate sequence out of the un-quantized B output.

Any ideas?

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Post by Broadwave » Sat Aug 15, 2015 11:52 am

finnurbjarna wrote: When set to 8/2 I'm not getting a separate sequence out of Quantized Output B, only the same as out of Quantized Output A ...

Any ideas?
Working OK here... I'll have a peruse of the schematics, and see if there's anything obvious it could be - I'll be back.

Hmmm... The only obvious thing I can see at the moment is Z30 A, B, C & D (input & output channel selectors) which switches between channels A&B - That would be my first port of call :hmm:

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Post by finnurbjarna » Sat Aug 15, 2015 1:48 pm

Excellent diagnosis!

I replaced Z30 and it now works (I had previously suspected Z33).

Many thanks. :party:

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Post by elmegil » Sun Aug 16, 2015 12:49 pm

So I hope to be selling some gear to get the cash to buy the parts I need to do this (hope to get it done before knobcon), so I was reviewing my mouser cart....

The Cherry Switches ( MX1A-11NW) are backordered, and "report manufacturing delays".

Does anyone have an alternative that will work?

Edit: actually, looks like Digikey has over 10k of them in stock... whew...

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Post by sduck » Sun Aug 16, 2015 1:32 pm

Mouser has all the other kinds of cherry mx switches - they come in a variety of "colors". Mechanical keyboard geeks like me will know this, but the different colors represent the differing forces, depths, and such needed to activate them - keyboard enthusiasts tend to have favorite styles (mine is blue). As far as the 1601 is concerned they'll all work equally well.

These are the blue ones - 540-MX1A-E1NW

(don't ask me how many mechanical keyboards I have here)
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Post by elmegil » Sun Aug 16, 2015 2:14 pm

Thanks. Interesting that Mouser's "show similar" didn't really get me there.

Can you describe the mechanical differences between the black & the blue?

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Post by sduck » Sun Aug 16, 2015 8:37 pm

Blacks are the ones with the most resistance, and don't have a discernible "notch" feel when they activate. The blues are about a medium resistance, and have a little click when they activate.

https://mechanicalkeyboards.com/faqs.ph ... difference

BTW the shop that hosts that chart is local to me and are terrible enablers. (I've bought 4 Ducky keyboards from them)

(typing this on a steelseries M-800 that truly sucks, but has really cool rgb backlighting)
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