DeltaLabs Compu Effectron 1700 Restoration

[tchgtr]

There is not a lot of info about these on the net, so I thought I'd share my experience for anyone else trying to get one of these up and running.
Purchased this for very little via Craigslist last year in non-working condition, and opened it up to find a bit of fuzz on and around the depleted lithium memory battery, and a blown fuse.
All Electronics just happened to have a replacement battery (man, I love that place), and purchased some fuses (.1A/250V) from some guy on E-Bad.
After cleaning up whatever corrosion I could find, and replacing the fuse and battery, it would start up and work fine, but most of the time it was powered down it would blow the fuse. I tried various electrolytic cap replacements (PSU and anything that looked stressed), nothing had changed, and I soon ran low on the 5 fuses purchased, and put it on the shelf, figuring I would ask the friendly folks here on GroupDIY for some suggestions on how to deal with it.
Recently, I found some more fuses at a local store and opened it up again to try it one more time. The new fuses were rated the same but the internal element was different, looking like a wire wrapped around a central core, instead of a very fine filament as in the first batch I purchased.
Lo and behold, I have cycled it about two dozen times now, and it seems to be working perfectly.
Lesson learned.
I like the sound of it, and read that it uses the DSD digital format, instead of PCM, which seems to give it a more natural sound, without hard edges. Closer to tape. It's a bit inconvenient, in that it doesn't remember certain parameters when shut down, which is normal as far as I can tell, and basically needs to be reset every time you turn it on. I/O volume, patch number, and other info is lost, and reset to basic settings.
Manuals are also hard to find, so here is the way to get into the unit after restarting:
Wait for the screen to go from 1111 to 0000 then hit Enter. Press Recall, and then a three digit number corresponding to the patch you want, and hit Enter again. Voila! Ready to go.
From there you can scroll with the up or down keys to different patches in the same group or press different parameter buttons to change settings.
As always, this place is invaluable to me, and I hope everyone is having a good 2017 so far.
All the best!

 

[radardoug]

The battery would be in there to store settings. Otherwise theres no point in it being there. Two possibilities: The battery is not holding up the ram memory. Second, you need to press a store button.
Look for a ram chip connected to the micro, and see if it still has battery voltage on it when the unit is powered down. Also check all the other legs for voltage, maybe it has incorrect voltages on pins like the write enable.

 

[mjrippe]

The first lot of fuses you had were "fast blow" with a single thin conductor.  The second lot were "slow-blow" with a coiled conductor.  A fast blow fuse will fail due to the inrush current at power-on.  A slow blow fuse will survive that initial current rush but protect against prolonged excessive current draw.  Some devices specify the fuse type on the back panel or in the manual, others unfortunately do not.

 

[tchgtr]

radardoug-it took me about 20 minutes of trial and error to figure out the procedure for storing patches. First Recall, then create your patch. Next Store, and then choose the number location you want to use, then Enter. Makes complete sense. Shows how manual-dependent I am. Seems maybe the first 99 patch locations are for storage.
Recall, plus the location number, plus Enter gets your patch. Once there, you can just scroll to your memory location. If you choose a location with no patch stored, it goes to zero after you hit enter.
Unfortunately the I/O volume info is not stored, but all other parameters are. I can deal with that.
Brilliant to you, d'oh for me.

mjrippe-this occurred to me, but when I searched for slow-blo fuses in those values, the only ones I could find were 5x20mm, which were not the right size. The ones that work say "fast acting" on the packaging, adding to my confusion. Of course you are correct, and now I know to look at the element in the fuse itself.

Thanks to you both.