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iamsetsetiam
New member
Hi Sweetbeats. Just wondering if you've worked on, disassembled the Tascam 788. Thanks.
Portland is not terribly far, but I’m not up that way very often, and time to hang with people is not something I have.@sweetbeats - i see you're in the PNW and am hoping you're local to Portland - just got a 388 in good condition that hasn't been used in 20 years, can't record or play back. Would be good to hang - I can't DM folks tho probably because this is my first post. Just putting it out there...
Otherwise reading this entire thread, and diving deeeeeep.
Well for sure the cabling is long enough to do the lense replacement, I just can’t recall how much of the meter array you have to dismount to get the 5, 6, 7 & 8 meter block out. The wiring for the lamp power and signal to each meter comes from the right end of the meter array as you look at the front of the unit. Of course the signal wiring for each meter goes to each individual meter (as opposed to daisy-chaining), but it’s all bundled together in a trunk, and then what’s even more restricting is the lamp power wiring which does daisy-chain from meter to meter. I’m pretty sure you have to probably dismount the 8 PGM meters, but can maybe get away with leaving the STEREO meters in place. You’ll know for sure when you get in there.Thanks Corey! I was hoping I could do it like that. I went back to your first images of this thread and although it wasn’t specific to that removal, I saw a few things that led me to believe what you say. I hope that the cable is long enough to be able to safely work with it and I’ll update you on my progress.![]()
Here's the replacement unit, hopefully that lead is long enough and I can just simply attach the new "glass"! OR, if it's just these two connectors, I may just be able to do a full swap. We'll see this weekend when I have time to dig into it.Well for sure the cabling is long enough to do the lense replacement, I just can’t recall how much of the meter array you have to dismount to get the 5, 6, 7 & 8 meter block out. The wiring for the lamp power and signal to each meter comes from the right end of the meter array as you look at the front of the unit. Of course the signal wiring for each meter goes to each individual meter (as opposed to daisy-chaining), but it’s all bundled together in a trunk, and then what’s even more restricting is the lamp power wiring which does daisy-chain from meter to meter. I’m pretty sure you have to probably dismount the 8 PGM meters, but can maybe get away with leaving the STEREO meters in place. You’ll know for sure when you get in there.
Notice there are cut wires at the left in your pic of the back of the assembly…I circled them in red. So, yes, you have connectorized connections, but there are hard-wired connections too. And I think your replacement assembly is for meters 1, 2, 3 & 4. Notice the vacant solder lands at the other end at the right…I circled in green. These lands are populated with the wires that carry the lamp power to meters 1, 2, 3 & 4 on the 5, 6, 7 & 8 meter bank. They are vacant on the first bank. I don’t see any reason why you won’t be able to just swap lenses…you’ll just likely have to spend a few more minutes dismounting the first bank of meters. Just get in there and get started. It’s not that difficult. You can do it.Here's the replacement unit, hopefully that lead is long enough and I can just simply attach the new "glass"! OR, if it's just these two connectors, I may just be able to do a full swap. We'll see this weekend when I have time to dig into it.
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I recently bought TWO 388s for $100 bucks.
…at first, the transport wasn't working on either. I did the reel servo adjustments (tension arm, winding speed, etc) and both came to life - Play, FF, RW, counter, etc. Everything was going well.
I tried my first recording and although I'm sending a strong signal (meters bouncing in channel and main, great sound in headphone/stereo/mon mix) however, the signal I get on playback is muffled and barely audible…I get exactly the same result on BOTH machines. My first thought was user error - if I'm seeing it on both, then I must be doing something wrong.
-It plays prerecorded tape just fine - so that would rule out the PLAY/RECORD head, no?
I'm fairly certain that it's not a playback/RMX issue as I'm getting the same muffled garbage from headphones, mon, aux, stereo outs. It seems that it's just not getting recorded well.
My suspicions are:
-Tape quality (although these are not ultra high quality, I should be getting something beyond a muffled rumble, no?)
-After sitting so long the bios pcb 1 crapped out…Maybe I pull this and check the capacitance on the components - might have a flat capacitor or three?
-Somehow i've wonked up the tape tension - I don't have (nor have I ever seen in real life) a tentelometer. However, this seems unlikely because prerecorded tapes work fine.
I’ve always called them mini Molex connectors. I think they are made by Molex. I’ve never had to purchase anything for that because I have so many connectors and plugs and headers around here from units I’ve parted out. But you don’t have to get the exact same connector style. Anything that has the same style (square) pins of the same size, and the same pitch will work. If you have a dial caliper you can measure all this with reasonable accuracy and narrow down your search on Mouser or Digikey or whatever. And maybe try narrowing the search by Molex. I might be wrong, but if I’m right that should help.Weird - I was going to post an update here (and hadn't yet) and @akieffer mentioned I fixed it by replacing the PCB. I was able to confirm that all tracks were recording by swapping the rec/play cards around - the channels not playing back moved with the cards. Bought two replacement cards off ebay and I am up and running! On to calibration!
I hope you get it figured out akieffer!
Another question - if I were to make a test harness - anyone have an idea on the pin connectors I should be using? Looked up the part number and couldn't find anything. I know they are about a 3mm pitch but there are other connectors on mouser damn close to 3mm and wanted to make sure I'm getting the right ones.