Tascam 122mk3 Full Rebuild

[@JamesE707]

Your video reminds me that I do need to get hold of some dentist's tools, or equivalent. They're so handy for delicate oiling operations.

[@asbcustom]

My dentist keeps a stash for when I go around begging.

[@JamesE707]

Hi Peter, just noticed this new video. I'll be back Thurs/Fri/Sat to watch it in full! :)

[@asbcustom]

Thank you for your support!

[@JamesE707]

Hi Peter, I'm going to stick my neck out here - Not wishing to be controversial, but I remember suggesting in a forum that the tape guide on the record head doesn't really guide the tape, despite being called a 'guide'. If the said guides were that important, then tape height and azimuth would be drifting widely while the 'guide' was fighting with the edge of the tape to keep it in line. If anyone reading this has a lot of ferric oxide on their head guides, then your head/guide is misaligned. So what keeps the tape in line?: Answer - principally the cassette guide wheels/rollers at the extremes of the tape path. A good capstan and pinch roller alignment, with correct tensioning also helps matters. A good dual capstan system like this Tascam makes an even better job of tape flow. This is why, using good tapes with good shells is important, but the issue of azimuth consistency doesn't end here. I think, the guide is only useful when we first press Play if the tape is not tensioned enough. Anyway, there we go. ;o)

[@asbcustom]

No controversy here Mr. James, I believe my statement in more than one video is that tape guides are akin to guard rails, not railroad tracks. Likewise, audio forums are like the description I've heard of helicopters, "ten thousand nuts and bolts all trying to fly apart at the same time". All one has to do is look at the NAB manufacturing tolerances for tape, and guide. The maximum width of the tape must be no greater than the minimum width of the guide. In practice, they never come that close, the tape is more narrow, and the guide, wider. Here for you is taken from page 14 of the Denon DR-M44 service manual: "1. Tape Transport Check Load the transport check cassette (MC-112C). In the operational mode, illuminate the fixing guides of the R/P HEAD with a lamp and check sure the tape edge does not come in contact with the tape guide section. The tape -transport is the most important element in determining the performance of a cassette deck." This is one of many times I've seen this written, albeit, a bit more precisely. Of primary importance is the squareness and yaw of the capstan to the travel of the tape, the slightest skew will throw the tape into the guide. The better transports use machined castings rather than stamping and swaging.

[@JamesE707]

Peter, we use the same LCR meter!

[@s11874]

Love the videos Peter. Apologies if this has been asked before, but I’m curious to know what brand/kind of microscope you use to record your videos?

[@asbcustom]

Thank you for watching. This was a Nikon Labophot trinocular (old school) with a couple of well regarded Nikon APO objectives from when I was doing a little photomicroscopy. The capture was a Nikon Z30 with an adapter that I 3D printed as an experiment, it seems to do the job okay.

[@nicolasfromk-town9333]

I have the same thing with the coating. You can use PCC (printed circuit cleaner) and tissue paper and go over with a brush. Or Aceton first, then Thinner and off with alcohol.

[@asbcustom]

Thanks, I'll give it a try.

[@akosszenasi1856]

Hi, can you help me please? This insulator around the magnetic rotating unit (7:15 in your video) completely aged and it falls apart - so missing. The deck doesn't works. :( Can I replace this insulator somehow? For example with siloplast - silicon...? Thank you! Regards - Ákos

[@asbcustom]

Akos, I'm looking at 7:15, are you referring to the material between the two slots that insulate the winding leads?

[@akosszenasi1856]

Yes! Is it important for working? I mean it can be the problem with playing if it missing?@@asbcustom

[@asbcustom]

I don't know what material might be available to you, I used a simple contact cement that stays pliable after it dries. If the motor leads are shorted against the frame, then yes, it could cause a fault, but that's probably not the actual issue.

[@akosszenasi1856]

Thank you very much for your quick response Sir! :) @@asbcustom

[@asbcustom]

Happy to help. If your motor board hasn't been recapped, that will probably fix your problem. It's a known issue with these, all will fail at some point. Good luck Akos!

[@naededi6824]

Hello & greetings from germany. Very great Job, it's a pleasure to show your videos. Thanks. For any month I repair/rebuild the same model and my problem was to find a good idler rubber. I found only one on ebay with poor quality and not so smooth like yours. The next point for me was the motorboard, I changed the SMD- Caps, but in different videos i've seen different caps 3,3 µF polarized, on my board the caps unpolarized. I don't found any Information in my service manual. If you have any Information for me, where can i found a good idler rubber and for the caps irritation, I will be happy. best regards from naededi (I like Revox )

[@asbcustom]

Greetings Germany and thank you for watching! The 3.3μ are non-polarized. I can send an idler tire to you, please contact me through the e-mail link on the "About" page or through my Website.

[@hassanshahid9776]

Greetings, I have the same deck in brand new condition. It was left unused and I found that the famous "Gear C" was crumbled and was replaced. The deck does not output music signal from the tape and No indication on the VU meters as well. I tested with headphones and I can hear the tape hiss when played, but no sound signal. What could be the issue? Your help would be Much appreciated!

[@asbcustom]

Thanks for watching. You say you can hear tape hiss? Are you sure there is a recording on the tape?

[@hassanshahid9776]

@@asbcustom Yes I've tried multiple tapes. I'm not sure if it's the tape hiss or some other harmonic noise. Though, It is affected by the Dolby NR and only audible when the tape is played.

[@asbcustom]

Well, tape hiss and harmonic noise are a very different diagnosis. I don't know, check all the connections you removed to service the transport, check for other loose connections, check to see if signal passes through the monitor circuit, make certain the mode switch is in "auto" not "input". There are an infinite number of possibilities.

[@hassanshahid9776]

@@asbcustom Yes, every switch and apparent possibility checked. One more thing, I can say that the signal passes through the head because I have a head demagnetizer, and it shows on the UV meters when it gets close to the head. But no sound from the tape.

[@asbcustom]

Does it pass an input signal?

[@nguyenvanlai4679]

Tôi rất mong bạn hướng dẫn cách làm .chỉnh tốc độ quay nhanh, chậm của tacam 122mkii .cảm ơn bạn nhiều.

[@asbcustom]

The 122mk2 is a single speed deck. Do you mean the 122?