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Got back to debugging this misfiring CE1 today.
I first spotted & cleaned up a short on the PCB that seemed to fix any issues of the bypass 3pdt. To be 100% sure there wasn't a secondary problem with the bypass 3pdt I replaced it.
The output jack was no longer shorting when the effect was on by then.
Brilliant, it was audio probe time. Signal made it to the BBD input but not the output of it, so I dropped in a new one & it worked, signal to the output jack.
The rate LED's were flashing for both vibrato & chorus mode again, not just vibrato mode as it was when I last looked at this thing a couple of days ago.
At least by the time I called it a day today, I had a guitar in & hearing chorus.
However, there's still a few issues to sort out before I can move onto reintroducing the stereo out jack & any mods one by one.
Firstly there's a pulsing hum present in both chorus or vibrato mode. Also, not really getting a vibrato mode.
The Level pot has a scratchy weirdness to it, but works. But for a new one doesn't seem right.
And the Recom power module was starting to get a bit warm after a while, which may or may not be normal.
I'll have a think about these last few things for a while & then get back to it when I can.

I had another quick look at it before calling it a day. All the op-amps tested OK. Turns out there was nothing wrong with the rate LED/s either, they just weren't working because the ground lug on the bypass 3pdt was no longer happening for some yet to be determined reason. Hopefully my fears of a surge when the power module failed aren't likely now though.
So, for now, I moved the rate LED ground back to the main PCB to get it going (even though it keeps flashing in bypass mode from there). There's still an issue either with the bypass 3pdt possibly being faulty or something elsewhere causing a problem with that ground lug. The other odd thing with the rate LED is it's only flashing in vibrato mode now & permanently on in chorus mode.
One other serious thing I discovered was in effect mode the output jack is shorted.
Far out, I've made dozens of effects, but I haven't borked one this bad before, I'll have to give myself an uppercut.
Definitely a few things for me to work through later.
Next time I look at it I'll disconnect the middle lug in that row of the bypass 3pdt & check it's switching properly & go from there, but it sounds like that will be the least of my worries. I'm not even at the audio probe stage yet...

More than another week later, I've finally got around to looking at my non working CE1 again.
I stripped it back to bare bones, took out the 2 mini mod PCB's (for blend & hi/low toggle), disconnected the stereo out jack & then socketed in a new Recom power module.
The bypass LED was still working but the flashing rate LED/s weren't. A quick voltage check on those told me they were getting the correct fluctuating voltage, so considering it's a situation where the original power module burnt out (& stunk me out) a few weeks ago, it's looking like it probably caused a power surge & wiped a few things out with it.
I'll have to continue later by checking the IC's in my IC tester, possibly replacing all the transistors etc. I'll get there eventually, it's just been quiet in the CE1 thread so I threw a post in for those watching it.
I did plug a guitar in this time, got no wet signal through it, but was getting a ticking noise in one of the modes (chorus or vibrato) whose ticking noise rate was adjustable by the speed pot, so at least some of it is working. The Recom wasn't overheating this time around either, nor did anything else then or now, but it definitely looks like there will be a few parts to replace when I determine which ones exactly. I'll have any replacement parts needed on hand, so no worries there.
I hope Skyled had better luck first go, his list of mods was much more complex than mine.

More modulation banter after another weekend...
I got the Dod Flanger 640 finished. It's successfully converted to DC jack, rocker power switch now an identical DC model that serves as effect on indicator, true bypass, all old parts apart from resistors replaced, so it's basically finished.
One minor prob, audio probing the signal stopped at the input pins of the SAD1024. I have 3 of those chips, 2 new & one that was tested working before being mailed to me, so the BBD isn't the problem...
In the 80's the SAD1024 used to fail every year or 2 in it, so I'd just go buy another for $10 & it worked as good as new. Last time it happened, replacing the SAD1024 didn't get it to fire up, tried a few more new ones, still no luck, so I replaced the other 3 IC's in there as well before I gave up & it went into storage ever since. What I think happened/what I think the problem likely is, would be I think I replaced the original cd4013ae with a cd4013be at the time. It's all in the suffix. I had similar issues last year getting the madbean Electric Mistress to fire up as well, which turned out that the cd4049 was the difference of it working or not depending on the chips suffix being "be" or "ube". Also in that one the same problem happens with the LM311 chip. The "n" or "p" suffix on those has to be the correct one too or it wont work.
So, I've got some cd4013ae's on the way from the UK which should hopefully do the trick.
Looking at the data sheets, there are some differences between the "ae" & "be" version 4013's, same pinout & function, but propagation delay is 45ns on "be" and 350ns on "ae". That's the first potential problem. Seems to be differences at clock input frequency at different voltages & other subtle differences between the 2 chips. I think I've seen enough without checking max frequency, load capacitance etc. It only takes one minor change to throw the whole circuit out of wack, as evident with the Mistress circuit, so it's looking like the 4013 chip variant has been the problem all along. At least now that's sorted I can get back to the CE1 & get that one going....

Over a week since last CE1 update, so just a quick one. The replacement Recom has turned up so I'll turn my focus back to sorting out my CE1 in the coming days.

I've been doing a complete rebuild of another golden oldie this week, Dod Flanger 640. I used to be able to get a great chorus out of that one too, as well as strong jet to mild flangeing. So far I've replaced everything but the resistors, also got rid of the AC power cable & built a DC power supply for it. Those DC jacks fit the former AC hole perfectly. Had to replace the AC rocker switch (with internal light) with the DC version from the same manufacturer (or the light wouldn't work). Instead of using that rocker light to indicate on/off AC power, might use it for wet/bypass indicator instead, saves drilling the original enclosure & more useful that way.
Everything will be the same without the AC cable & without going through that noisy old internal transformer (spikey SAD1024 killers they were). Most of the old capacitors still tested OK, but they're all replaced regardless considering they're approx 40yrs old.
A ceramic capacitor these days can be as small as a match head, but one they used then was a higher voltage one the size of a small coin. I only mention it because it literally squished between my fingers like a sticky lollie that was lost in the back of the 2nd drawer for years, I've never seen a part so age-weary it disintegrated like that before.

Also got a few dirt boxes out of the way from my pile of "to do laters" that I'd been putting off.
A Tonebender Mk3, using AC125 transistors, also put the internal trimmer as an extra 4th knob as it added more variety & was wasted otherwise.
Then a Nobels ODR1 (overdrive) from an Aion PCB.
Then a Guv'nor (distortion).
Those 3 only had minor things preventing them working first go, so didn't take me long to finally get them running. All sounded OK too, I'm usually fussy with dirt boxes, most can sound crap to me.

Apart from that there were a couple of VFE builds. They both had the same problem I've had with 5 out of 6 VFE builds. The switching boards weren't working. Probably just bad luck with relays, but the actual main PCB's sound great when working though.

Anyway, I just have to wire up the freshened Dod 640 PCB over the next day or so & pop in the fresh IC's, shouldn't take long, fingers crossed. Then back to the CE1 after that...

At the time of writing, it's nearly a week since I ordered another Recom RD-1215D power module. It's looking like it wont show up in the mail until next week. When I get it, apart from using a power adapter instead of a battery, I'll temporarily disconnect the 2 small mod PCB's & get the main PCB going first.

The Hi/low switch mod runs off the same 14v voltage as the main PCB, which I wired to the positive side of C12 based on the schematic.

The Blender PCB (from pedalparts uk) might be an issue in this case because it runs off 9v, not 14v. I had that connected straight from the DC jack, bypassing the Recom & main PCB altogether. So I've developed a concern (or a doubt) that instead of it being OK to do that, it may have added an extra 9v to the main 14v or caused another problem that way.

They're great Blender PCB's though, I've used them in a few other modulation's, but ones that run at 9v, so no potential voltage conflict previously. They should be fine to run at the same 14v as the main CE1 PCB, as the only voltage sensitive part on it, a 2n5952, can handle up to 25v. So after I get the main PCB going, I'll run the Blender off 14v as well this time around.

Going off topic for a moment, in the meantime, I grabbed a couple of pedals I'd built a while ago (from a pile of awaiting calibration/waiting to be fixed). A VFE Phaser bought from Madbean & a Carlin Compressor.
The Phaser just needed a trimpot adjustment done by ear, so it's done. I like it. It's probably on the milder end of the phaser spectrum, but that means it's actually usable. There's quite a few settings & different stages compared to the old one-knobbers & can even get a bit chunky sounding if that's your thing. There's nothing like the Doppleganger though, but that's another story...
The Carlin Compressor is one I hadn't heard before, so I didn't know what I was in for. When I quickly tested it with a guitar months ago, all I got was distortion & not a usable one, so that's why it was put aside. Going back to it now, it's meant to be a distortion with a sustain knob. It did require a trimmer adjustment so the dist knob goes from mild overdrive to more saturated distortion. Depending on how the trimmer is set, the sustain can be a bit uneven & start making the whole thing sound spatty or pulsey (unusable), but I got it as good as I could & it is what it is. The sustain is quite long, but I'm still undecided on the gain aspect, so I might need another go at the trimpot later or to see how it pairs with another dirt box or something.

Hopefully I'll get the CE1 sorted next week & report back on the mods.

Another day, better rested...so I did the LED mod & it does work. However, after 20 seconds or so the Recon power module failed out of the blue. It wasn't related to the mod because I only moved the LED ground from the 'always on' point of the PCB to an existing ground point which is on the bypass switch. Also the positives of the LED's & their +v from the PCB were just moved to 3 unused lugs of the mode switch, so all unrelated.

Anyway, I was only running off a 9v battery for testing purposes, so maybe it was draining too much current, especially if it had dropped far enough below 9v (it wasn't a brand new one, might've sagged down to 6 or 7v by now). When the replacement Recon turns up I'll use an adapter instead & if it does it again then there's some troubleshooting ahead before powering it up again.

There's no visible shorts or anything like that, but with 2 extra mini pcb's in there taking power (hi/lo switch mod and blender) my guess is too much current drain & possibly too much pressure on the Recon module. It's specs say the input voltage range is 10.8 to 13.2V DC. My local retailer puts it at 9 to 18v, so I must've been at absolute minimum at best with a battery, which probably wouldn't be good....as I discovered.
It's not a major drama, I've already taken the module out as I wait on the mail, it's just disappointing I didn't get as far as plugging a guitar in & I wasn't able to verify the other mods today. But, at least the LED's, the LFO & the rate knobs are confirmed working.

Just adding to my previous post.

I haven't worked on mine again yet, but I remembered it's difficult (or impossible) to fit those 3pin dual-color LED's in those common chrome bezels many of us use, so I thought I should mention that. Most (if not all) only have 2 holes in the plastic holders that come with them, especially the 3mm ones. Even if they had 3 holes, the legs of 3-pin LED's stick out sideways near the top & wont push in. I know many of the larger 10mm bezels have the holders for 3-pins, but not so sure about 5mm. I'm sure any could be used without bezels, I just prefer the LED's locked in place & also to match my other humble builds.

I've already drilled & installed 2 x 3mm bezels, one on either side near the stomp switches, for mode & bypass, so as a simple workaround for mine, as well as an easier approach to anyone that does it later, I'll just use those 2 side LED's to show the mode instead of a single dual-color LED.

That means 2 negative wires from A1 of the bypass 3PDT to the 2 separate LED's instead. Then the 2 positive wires from those 2 LED's to the Ch/V 3PDT (B1 & B3 respectively). B2 to the Ch/v positive LED pad on the PCB as described above in previous post.

For the bypass LED, the simple solution would be to drill a 3rd LED hole for a 3rd 2pin LED. Well, at least they'll all fit the various bezels around...

Hopefully the above helps others do theirs better the first time around or those that have finished theirs can go back & do it too. It'll still look OK with 3 LED's, so I'll just put the 3rd for bypass in the middle somewhere, maybe use a 5mm instead of 3mm like the other 2. Best of all no flashing in bypass mode & the rate LED becomes a mode indicator as well. Maybe increase the rate LED's CLR resistor from 10k to 15k to tone done the brightness of it a little. It's extra noticeable because it flashes.

For anyone interested, at the time of writing, this is an untested Ch/V LED (not bypass LED) mod idea.

I finally got around to wiring up my attempt at this chorus.
I haven't even plugged a guitar in yet, but before I did put it aside (was too tired to continue) I connected 9v to at least check the LED's were working. They were.

As the Ch/V LED was always on, even in bypass mode, I had a quick look into how to sort that out (because admittedly pedals that do that drive me nuts) & so it's why I had this idea:

Going by the schematic, B1/B2/B3 of the Ch/V 3PDT don't appear to be used by anything in the circuit.
So the idea is to use a 3pin dual color LED, which not only swaps color depending on Ch or V mode (so the user knows what mode it's in at a glance), but stops flashing altogether in bypass mode.

First to keep that flashing LED off in bypass mode (if you choose to do so). It looks like pulling out the Ch/V LED's negative wire from the PCB & reconnecting it to A1 of the bypass 3PDT should do the trick. Simple as that.

If you also wanted a dual color LED, that wire from A1 of the bypass 3PDT would then go from that bypass A1 to the longest lead (common, the middle one) of a 3pin LED.

Then instead of the positive Ch/V LED wire going straight to the LED from the PCB, connect that wire from where it is on the PCB to B2 of the Ch/V 3PDT. The remaining 2 leads of a 3pin LED (both positives for their respective colors) should then go to B1 & B3 of the Ch/V 3PDT.
Whatever color dual LED you use or what color you want representing chorus mode or V mode is up to you, red/blue, blue/red, red/green etc.

As I said, I'm just too tired to persist with it for the moment, so I'll hopefully confirm over the next few days (or week) when I get back around to testing this idea out. Not to mention any trimmers, possible troubleshooting etc. Hell no, not now, must eat & sleeeep....
Anyone cluey enough can probably verify it at a glance anyway.