I used 2N5485. Different pin out, so they go in backwards, but seem to work.
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Just did a layout with JFETs, and pretty sure 2N5457 and 2N5485 both use drain/source/gate order. The first datasheets I found agree:
(you can usually swap drain and source on JFETs but gate isn’t in the middle)
As long as you’re within the max specs, the most important properties for a JFET tends to be Vgs(off) aka Vp and Idss and the former is at least somewhat close (-0.5 to -4.0 V for the 2N5485 vs -0.5 to -6.0 V) while the latter differs more (4-10 mA vs 1-5 mA). Note that they’re not very precise devices, so if there’s no trimming procedure odds are the circuit is fine with either (or the designer just tested one, and you’re kind of screwed anyway).
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The board is made for a BF245A, so it’s reverse of that.
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So I build the SubOscillator some time ago.
As I had room for 2 on the same board (SubOSC for Crave and other equipment) I build 2 but lacking a second CD4013BE finishing the second suboscillator had to wait. So after a while I received the 2nd chip (Mail Day Thread) and this week I added that to the circuit. Alas it turned out the 2nd sub oscillator didn’t work.
[debug mode on]
1: I checked the 2nd instance of the suboscillator circuit comparing it with the 1st and couldn’t find a difference.
2: I checked all power connections. All voltages were according to what I expected.
3: I tried the chip from the first sub oscillator in the 2nd and experienced no joy.
4: I tried the chip I had put in the 2nd sub osc in the first sub osc to see whether it was still alive and to my great surprise it didn’t produce a signal but worked when I touched the resistor in the feedback loop /Q -> D with the tip of my oscilloscope probe.
I then found that I could get the 1st circuit to work for this chip as well after adding a small capacitance to ground ( which my oscilloscope probe was doing as well ).
But of course this left me puzzled. Why would the one chip work without any problems while the 2nd one needed this capacitance? Because the chips were made by different manufacturers I attributed the difference in response to that.
[debug mode off]
[resolution mode on]
Then I discovered that both instances of the sub oscillator lacked one essential connection. The GND pin of the CD4013 had not been connected ! After remedying that, all worked well.
Problem solved.
[resolution mode off]
[flummoxed mode on]
But why did the 1st sub oscillator work at all when it also was lacking this seemingly essential connection? Maybe it was ‘naturally grounded’ ?
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LOL… Lost a few grounds myself over the last few months…
Last night I soldered up my Gate2Trigger
This morning i decided to give it an audio test ( need to get my oscilloscope to test properly)… So I went off hunting for the AS3310 to put in it, before testing with the chip I decided to do a power rail sense check so pulled up the Pinout for the AS3310. I then checked the voltage and there was nothing… Ground did not seem to match any other ground…
I then put the AS3310 (ASDR Chip) back in the packet and pulled out a LM324 OpAmp, and referenced it’s data sheet against the power rails. Which was fine…
Having successfully not smoked a As3310 and seemingly possibly got the trigger module working I thought I would move on to building…
I got most of the components down and came to the jacks. For some reason my mind was playing tricks on me, I thought the jacks had been flipped on the board and were on the wrong side… I got my thinking cap on, I had already soldered the daughter control board and that was going to need flipping too. so I did all that. and then later realised that It was all correct in the first place. DOH!!! So got to try and unsolder lots of stuff and flip it again!
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Tacked the 8-pin DIP socket and forgot to finish soldering it before mounting the jack sockets on the #1161 Buffered Multiple, made it a bit hard to reach the last few solder joints…
BTW those LEDs need long leads to reach all the way through the front panel, I didn’t need to trim them at all after soldering. Had to mount them “backwards” to get red on positive voltages and green on negative.
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yeah the LED’s on the MIDI2CV need Super Model legs too, …
Rob
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That second photo looks like you’ve gone all Ciat-Lonbarde over your PCB.
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Yeah haha! I really like that style, but not really easy to reproduce 
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Had the pot cluster problem now and then with guitar projects. Failing getting your hands on new , smaller pots or pots with long shafts you can in extreme cases cut away the pot shield and use washers… I did say extreme. 
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turn them 90 degrees and use fly leads.
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So. I forgot to order a transistor for the VCO (thought I had some but I guess not). I also needed to order a few ICs from a different vendor for the Midimuso module. Now I’m waiting on a handful of parts for three modules.
Oh. I also soldered all the wires to the ADSR jacks backwards. Good thing I double checked. Not bad as far as mistakes on these.
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don’t worry you will find them . weeks from now after you have ordered new ones and built what you are working on 
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I spent 5h debugging my VCO, on the first half is was clipping my scope’s ground on a jack socket that wasn’t connected at all… Then it took me 1h to realize that I ordered a DMMT3904, while I used an MMDT3904 for the layout. These two parts have a different pinout obviously…
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Anything a Dremel can’t fix, duct tape can…
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Good idea: Providing a BOM in your project documentation.
Better idea: Providing an up to date BOM.
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There has to be some sort of rule like:
Five minutes after you finish paying for a shipment from Tayday/Mouser/etc, you realize you need to order one more component.
Every time.
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