Tascam 122 Story...

[sweetbeats]

So I've had an Onkyo TA-2058 consumer cassette deck for over three decades...its been dormant for awhile, and, upon pulling it out recently to play some archived cassettes I discovered the capstan belt was dried out, stretched and slipping. I found a rubber band that worked to get through what I needed to do, and also ordered a set of new belts, but getting the old Onkyo out reminded me I've always lusted a bit after a Tascam 122...it sounds a bit silly but one of the main attractions for me was simply having a cassette deck that is rack-mountable. And then I liked the idea of some of the calibration trimmers being front-panel accessible. But most of what I saw available was the mkII machines, and the prices were always a bit rich for me and anymore they are just silly, plus it was just never enough of a priority since I rarely used a consumer format cassette deck for anything anymore. I guess the other ideation I had is that the Tascam would be easier to work on than the Onkyo. The Onkyo is a great three-head machine, but the construction is consumer which means the guts aren't well laid out for servicing...but its a good machine...I mean, it still works like a champ after all these years and only the capstan belt needs replaced. ANYway...

The past few weeks the Tascam 122 bug has been itching at me and I've been trolling auction sites and reading the manuals of the different generations of 122 machines...and I found myself drawn to the old-school first generation 122. My understanding is the mkII and mkIII have a better R/P head in them than the 1st generation, but they also have the direct-drive capstan vs. the belt-drive version, and the direct drive assembly is the same one that causes trouble in the 238 with the "jet-engine" runaway speed thing and its a potentially expensive fix if you can find a replacement servo board assembly...anyway...I had a 234 at one point and old-school was good with me...less complicated circuitry and fewer bells and whistles in trade for maybe better end-user serviceability. But as I studied the schematics I was kind of taken aback the original 122 has only one opamp in the entire stereo signal path...there are ICs for the Dolby B and HXPro processors of course, but almost all of the line amplification in the 1st gen 122 is discrete transistor-based, with an integrated transistor array at the output stage...relatively few coupling caps in the audio path...the power supply is even discrete...quite old-school...I started watching this one on eBay that appeared very clean, and clearly needed a capstan belt...I'm getting pretty good at repairing the cassette multitrack machines and so that didn't bother me. The price was right...should be able to recoup my purchase and parts expenses by selling the Onkyo...and I thought it was cool the 122 runs at 1 7/8ips ad 3 3/4ips...not that I would have a need to do cassette masters at 3 3/4ips, but...its cool...and the multiple line inputs, switchable sidechain for a dbx n/r unit...and its a nice looking machine. So I pulled the trigger.

Its missing one of the little switch knobs on the right...that's going to be hard to find...and a couple of the switch levers got tweaked at some point, but I can straighten those...I've verified the motors are in great shape, the capstan belt has melted, and it needs a new pinch roller (already reached out to Terry Witt and he says he can re-rubber the 122 pinch roller because it is on a metal core instead of plastic). The belts are readily available. It needs a new meter lamp for one of the VU meters but that is easy-peasy and I already have a stock of those leaded axial lamps. So I'm happy. But it got even better when I opened it up. More on that below. First some pics.

Here is the face...there are a couple scratches through the finish on the face, but they are minor...it looks good as-is and will easily clean up even better. This was a well cared for machine:






And here is the back...dbx I/O jumpers intact...again, clean and straight:




But then when I opened it up I was greeted by a roomy chassis with easy-access boards, and thoughtful component layout...big main transformer...




...and then when I looked at the capstan belt issue I was surprised...this thing has the largest diameter flywheel I have ever seen in a cassette machine...the spooling motor is the gold motor in the center...if you look just to the left you can see the top of the capstan flywheel you can see the top of the flywheel with melted belt on it...you can maybe judge the size of it by the curvature of what you can see...its maybe 3" in diameter? And look to the left of the spooling motor...those rectangular blocks...those are solenoids...the same solenoids Teac used for brakes, pinch roller and lifter actuation in many of the their open-reel tape machines...Teac used them in the 1st gen 122 for head assembly lifting, pinch roller actuation and spooling functions instead of plastic cam gears and a control motor...its relatively beefy...and makes nice positive *tchuk* noises. Me likey:




I captured a short video snippet of the solenoids in action:

YouTube


And this is a small thing but the left and right input level controls are coupled by a gear-driven mechanism to maintain stereo tracking...you can move them independently too, but if you want to have them track you just turn one and it smoothly drives the other...captured a short video of this too:

YouTube


Anyway, I really like my early generation 122...can't wait to get it fixed up and take it for a spin...but first have to get the Onkyo all ship-shape and find a new home for it.

Hey if anybody happens to have or know a source for the small black switch knob I'm missing could you PM me?


[EDIT]

I forgot to mention, because the 1st gen 122 was made in what I consider to be something of a more golden age for Teac/Tascam, the manual is *excellent*...comprehensive theory of operation section along with the typical sections...well written...attention to detail...a few years later this was not the case.

Oh and who could resist getting a free copy of Chicago's Greatest Hits Volume II with their 122??

 

[Findlay]

What a fantastic deck! I just looked up the spec on hifiEngine. Am I right in thinking you have the B version with dbx? Really interested in what you make of the recordings once you've worked on it. What a great project.

 

[sweetbeats]

What a fantastic deck! I just looked up the spec on hifiEngine. Am I right in thinking you have the B version with dbx? Really interested in what you make of the recordings once you've worked on it. What a great project.

Thanks!

Mine is not the 122B. The “B” has nothing to do with dbx n/r. Both the 122 and 122B have connections and manual switching for outboard dbx n/r. The difference with the “B” is that it has balanced I/O on XLR jacks in addition to the unbalanced I/O on RCA jacks and, as a result, differences in the rear panel layout. Otherwise the 122 and 122B are the same.

 

[j.harv]

Very nice! I have one myself that I got for very very cheap a few years ago. Still running strong.

 

[sweetbeats]

Very nice! I have one myself that I got for very very cheap a few years ago. Still running strong.

Oh cool!

Hey maybe you know...am I correct there is an idler tire for the spooling function? And if so do you know where to get a replacement for that?

 

[j.harv]

That I don't know unfortunately. Sorry.
I did open mine up, but I didn't end up tackling the tires. I just put in new belts. And that was around 7-8 years ago. So i'm a little foggy on the innards.
But now that you brought it up, I will get to the idlers sooner or later.

 

[sweetbeats]

I picked up an RC-71 remote for the 122. This is the 3rd RC-71 I’ve owned...one came with a 234 I used to own...sold it with the 234 after I refurbished it...then there was one that came with a 388 I bought...same deal...repaired/refurbished the 388 and flipped it and sold the RC-71 with it as a package.

Honestly I think this one is in the best shape of any of them, and it was only $35 shipped!



The connector pins are in good shape too! My experience is these are often tarnished or bent...



But every single one of them has been missing the strain relief... But no worries...I have new strain relief inserts that look almost identical to the factory part and fit perfect...and by now I have some experience with this repair.



That’s just a rubber grommet somebody shoved in there at some point after the original strain relief went AWOL.

I might try to de-yellow the transport control button caps...

 

[sweetbeats]

Long time no post on this thread.

I still have the original 122 that started this thread. I also have another non-functioning but better condition 122-B I got for cheap years ago…plan is to use the original 122 as a parts donor and fix up the 122-B. I have belts and idler tires to install, and Athan Corp is working up one of their top-notch pinch rollers to replace the original, which isn’t hardened or gooey, and seems okay, but I recently learned if they’re old it’s just better to replace them, because they may no longer be as flat and true as they need to be just due to use and age.

I recently had the 122 opened up to pull the transport and pinch roller and was reminded of a couple reasons why I like the first generation 122…and maybe this first one is a point of criticism for some…but the transport is almost more like a miniature open-reel transport, and I say that because, like, rather than one driving mechanism being responsible for actuating the headblock assembly and engaging the pinch roller for instance, like every other cassette deck I’ve worked on, there are separate mechanisms and solenoids for the headblock motion, pinch roller actuation, etc. And I think I mentioned this earlier in the thread but the solenoids are, like, the size you’d find in a smaller open reel machine…full size solenoids. It’s a beefy little transport. Now, critics will say the solenoids and separate mechanisms make for a less elegantly operating transport…well I don’t know…what I do know is the 1st gen 122 transport might be easier to work on, troubleshoot, etc. They were workhorses. All the 122 series machines were, but the 1st generation isn’t plagued by the “gear C” and capstan servo maladies of the later generation machines. And I’m still enamored but the fact the signal path is 100% discrete. And back to the transport for a sec, it’s not like it’s just old school and that’s the way things used to be…I’ve not encountered another cassette deck transport quite like this. Maybe I’m not well traveled in this area but it seems pretty unique. And lastly, for the sake of this post, and I’m kind of repeating myself here, but the service manual…I had it open today poking around to help advise somebody having some trouble with their transport control buttons, and I’ve been digging through the 238, 246, 388, and other even slightly later generation service manuals lately helping people, as well as the 122mkII and 122mkIII manuals, and they all are kind of sucky…you step back in time just a little before those above-named models and the service manuals were very thorough, well-written, relatively error-free, and had ALL the operational theory stuff. Like, if you don’t know what that is, it’s basically the service manual taking you beyond “here’s how you service the device, and here’s all the parts, and here’s the schematic diagrams” to here’s the “how” behind why it works the way it does…like it goes into rich detail about how and why pressing the PLAY button makes it reproduce the tape, what is happening electronically. And why does that matter? Well, if you’re machine isn’t working right, if you have a truly good service manual, you can read up on how it is *supposed* to work, like down to the component level, and not all technical jargon speak either…you get out the schematics and read the operational theory sections and you can follow along. It’s helpful and educational. And then if it’s not working you now have all sorts of information about what to check and test…the 122-B service manual is (ironically) 122 pages long. The 122mkII? 52 pages. So, it was in a golden era at Teac, and then something must have gotten cut in the budget because it all changed, and then we get service manuals like the 388 which has a bunch or errors, doesn’t explain things, and a complex machine like that really should have a corresponding comprehensive manual. Anyway, the 244 manuals are good, the 58, I think the 38…1st gen 122…