Tandberg Series 15 SL - looking for some info

[ablaumeise]

Hi there,
I just bought a Tandberg Series 15. Saw it, fell in love with it and just had to buy it. :)
Actually this is my first reel-to-reel deck - nevertheless I'm rather experienced in restoring vintage equipment (wrong brand for this forum, though *embarrased*).
I already fixed it up - a good clean, new lubrication, etc. Everything works and sounds fine now.
Found this forum while looking for a manual (which I found here - thanks!) and I hope this will be just the right place for my questions:

This is not just a ordinary Series 15, it's a "Series 15 SL". I couldn't really find out much about it, this (http://www.nrhf.no/TB-15.html) is about the only thing I came across. Obviously it's a special "class room recorder" with some extra features.
Noticeable differences are:
- the "Stop"-lever is missing
- it has two "Output Volume"-controls - one works as usual, no idea what the other one is for
- the labeling is slightly modified
- most interesting: It has a extra connector at the back that is connected to a bunch of extra components inside (e.g. the missing lever is operated by a relay - remote control?)

Does anybody have some more information? A circuit diagram for the remote (if there is one) would be great.

Another question (while I'm at it): I need new belts and a new pinch roller. Where can I get those for a fair price?

Thanks in advance.

[Njord Noatun]

This is a pretty rare unit to find outside Norway.

Regrettably, the database does not yet contain the OM for the TB-15 series. Without it, the best I can do is to refer you to the appropriate pages from the 1970 Tandberg catalog - click below.

13710 13711

It does not appear as though the SL version had a remote control - only the "F" models did. The only optionally available accessories for the TB-15 were a carrying case and a acrylic cover.

Hope this helps a tad.

PS! Welcome to Tapeheads!

[jdurbin1]

I have originals for the OM and service manual.

The OM doesn't address the SL version but the service manual does. Also covers the series 14 and the 15 GT and 15 F.

John

P.S. Nukes, check your files... pretty sure you have the OM and a schematic for the model 15.

[ablaumeise]

Thanks for your answers!
I actually downloaded the OM and the schematics from the Database - unfortunately both do not address the SL.

The SL I have seems to be a odd machine. It does match neither the description nor the photos from the catalogue - it is a 4-track model and, as I said, there is no stop lever.
I added some photos so you know what I'm talking about.
http://img195.imageshack.us/img195/9684/21006895.jpg
http://img155.imageshack.us/img155/8610/95255772.jpg
http://img243.imageshack.us/img243/5709/73780345.jpg
I noticed it says "SL-F" on the back of the unit, so it looks like this is a remote controlled unit after all.

John, does the Service Manual also mention the remote itself? Are there simply 4 switches (the connector has 4 pins + ground) or is it more complex?

[Njord Noatun]

Nukes, check your files... pretty sure you have the OM and a schematic for the model 15. Wow, I do - have to go in a clean up the file naming to add "TB" to those early reel to reels, to keep all of them together.

Incidentally, I received a donation of the service manual for the TB-15 (also covers model 14) overnight and it has been uploaded - very timely! The SM is in Norwegian, but at least we have the information in the database now.

[jdurbin1]

Not sure how that came out "Nukes" instead of "Njord", must have been the ever-helpful iPhone auto-correct feature *reelspin*

Nice pickup for the archives... think my original SM is the English version but as usual I have been too busy playing with equipment to get it scanned. Does the donated one cover the SL and other variants like my copy?

John

[Njord Noatun]

Not sure how that came out "Nukes" instead of "Njord", must have been the ever-helpful iPhone auto-correct feature *reelspin*

Does the donated one cover the SL and other variants like my copy?



The SM covers the standard versions of models 14 and 15, as well as the Model 15 "SL", "GT" and "F" varieties.

I was wondering about your use of the word "nukes" and concluded that it must be some esoteric expression of surprise, along the lines of "Holy Smokes, Batman!": Now I know better!

:-)

[ablaumeise]

Thanks a lot for the upload! The SM helped me a lot (after running it through google translator :P).
What I found out so far:
I was wrong, this is indeed a 2-track model. I was confused by the track selector - the OM says only the 4-track should have one.
Now the interesting thing is: Both channels can be chosen for recording and playback - opposed to the 'normal' 2-track the SL has switchable 2-track erase and rec/play-heads.
Even more interesting: Both tracks are amplified by separate amplifiers! There's a second amplifier in there that always amplifies the 'other' track - if track 1 is selected it plays back track 2 and vice versa. The selected track is amplified by the 'normal' amp (output via speaker etc.) while the other track uses an extra amplifier (output via the "Free Head"-Socket or pin 4 of the microphone plug). According to the SM the second 'output volume'-control should control the second amp…but right now it does absolutely nothing and the volume is stuck at a low level. Guess I will have to take a look at that.
So much for the 'SL'-part. But this unit is actually a combined 'SL-F'! *yes*
Unfortunately I wasn't able to figure out all 'F'-features yet. While the connector is labelled 'FP 22' the FP 22 (foot pedal) shown in the SM uses a different plug. For some reason my connector has a 4th pin with a +24V supply?!
What works so far: Pin 2 + 3 -> Stop (at least most times…).

@John: Any chance your SM covers the 'SL-F' (or at least another revision of the foot pedal) ? *reelspin*

Also:

I need new belts and a new pinch roller. Where can I get those for a fair price?
Any suggestions? Or could someone at least give me a hint which size the belts should be?
I really want to use this thing and not just stow it away - hence all these questions...

[jdurbin1]

Belts should be easy, Marrs Communications on eBay probably has them although I doubt he has ever sold one for a 15 SL/F!

They only had two versions of the figure 8 belt mechanism that I know of. It's a round belt and I probably have some if I look around but if Fred has one it'll be new vs. NOS like mine.

I will take a look at the SM for the remote info. The foot pedal shows up on occasion on eBay, may be the same one going unsold in fact. I have another accessory that may plug in there, the Slide Synchronizer 3:

http://cgi.ebay.com/Mint-extremely-rare-Tandberg-Tape-Slide-Synchronizer-3-/400082628124?cmd=ViewItem&pt=Vintage_Electronics_R2&hash=item5d26c86e1c

That one lets you sync a taped sound track with a slide show, and some of the earlier decks had a jack to start/stop playback as the slide projector signaled them.

John

[Njord Noatun]

incidentally, we received a donation overnight of the schematic for the RC-9, one of the Tandberg remote controls. The owner's manual is also in the database.

I do not if this is the remote used with the TB-15F or not - but it might; one needs to check the 1970-73 catalogs (approx.).

[ablaumeise]

Looks like this is really one of a kind - I checked all catalogues and pricelists in the Database and it is not mentioned anywhere!
The pricelists cover really every model except this - there's a 1521, a 1521 F, a 1521 Sl, but no 1521 SL-F.
It also looks kind of improvised on the inside: there's only one recess on the inside that is obviously intended for one option - either the relay board for the F or the extra amp for the SL. Yet they somehow managed to cram both boards into there…
Also, the labeling on the faceplate reads SL only and the labeling for the 'stop'-lever is still present (which I guess it is not on the F-model).
But still this is a factory unit and was not modified afterwards.

@Njord: The RC-9 is way too sophisticated for the 15. The catalogues only mention one remote: In the 1968 catalogue it's simply 'the' Foot Controller, in later catalogues there are 2 models, the 'TFC 1' being the one for the 15 (no idea why it is called FP 22 in the SM).

@John: The Slide Synchronizer most likely won't work with the SL as it uses the 'Free Head'-connector - which is an amplified output on the SL.
Thanks for the info on the belts, but in the meantime I found this (http://www.elektro-ersatzteile.eu/index.php?cat=c1491_Riemen-fuer-Tandberg.html&XTCsid=2131e280ad75a021b56c8cde35d6044d) site. According to them the Series 12 belt should also fit the 15. Does this sound right?

The deck begins to fail anyway - lately the Joystick doesn't work properly, the transport mechanism gets stuck all the time and the motor is noisy.
I think I will get new belts and a pinch roller and do a proper rebuilt while I'm at it. *reelspin*

[jdurbin1]

Yeah, the 12 and 15 probably have identical transports as far as the belt drive, anyway.

Njord, the RC-9 should be the hard-wired remote for the 9000-series and 10X/10XD.

John

[ablaumeise]

Looks like a general overhaul was really needed. In some locations (especially the function selector and the joystick) the old lubrication had become so hard I actually needed a knife to scratch it off.
I disassembled the unit completely and cleaned & relubricated everything. You wouldn't believe how smooth everything works now!

I think I also found the reason(s) why the remote control is not working properly: Rewind did not work as the corresponding microswitch was stuck, Start/Stop only worked occasionally as the spring for that microswitch was partially broken. Haven't tested it yet, though. The new belt still hasn't arrived - they messed up my order and only sent me the belt for the counter…

http://img829.imageshack.us/img829/8582/88443637.jpg
http://img291.imageshack.us/img291/525/61409129.jpg

[eclectiktronik]

Hi,

what you have here is the standalone language lab version (SL= SprogLaboratorium /SprachLabor). Tandberg used the full width of the tape in 1 direction - a form of half track stereo I suppose - track 1 being master programme, track 2 being for student recordings. This is the reason you have an audio output on the mike socket - you plug a headset (http://www.google.es/imgres?imgurl=http://www.urdile.cl/images/2-headset-full.jpg&imgrefurl=http://www.urdile.cl/cad-audio-m-84.html&usg=__zcWSifCPHTOCtk8whKAMS6nvIaY=&h=622&w=700&sz=71&hl=es&start=3&tbnid=pIK9vdX_vfFwMM:&tbnh=124&tbnw=140&prev=/images%3Fq%3Dasc%2Bheadset%26um%3D1%26hl%3Des%26cl ient%3Dfirefox-a%26rls%3Dorg.mozilla:en-GB:official%26biw%3D880%26bih%3D485%26tbs%3Disch:1&um=1&itbs=1) in there, set it recording and you hear track one played back through the phones and simultaneously record your responses on track 2. Maybe the two volume controls are used for master and student volumes - you probably need to connect a headset to test that. It would explain the lower level, to avoid deafeing the students!

The foot pedal allows 'skipback' , usually called 'Recap' on tandberg's language lab decks (http://go2.wordpress.com/?id=725X1342&site=eclectiktronik.wordpress.com&url=http%3A%2F%2Feclectiktronik.files.wordpress.co m%2F2010%2F03%2Ftandberg-is6-stud-panel1.jpeg&sref=http%3A%2F%2Feclectiktronik.wordpress.com%2Ff ound-tapes-language-lab-recordings%2F). This winds the tape back as long as the button is beld down, then drops into play to allow you to check and correct responses, and re-record if necessary.

The remote pause could also be used for teacher console remote start-stop of the student recorders in a laboratory; however as this is a standalone unit, it is more likely they included the feature to aim it at the office/dictation market, a typist would find the foot controls (start, stop, recap) very useful and this is common in dictation equipment.

Your series 15 was probably a domestic version of the series 10 machines which were full language lab decks - you may find this video of interest. (http://www.youtube.com/watch?v=vBMjADJ3INM). These could record simultaneously on master and student tracks, or in student mode, would be like yours - playback master track, recording on student track.
regards,
Ben

[ablaumeise]

Thanks for your interesting input!

I already figured out the use for the SL from the old catalogues. By the way, it is even advertised as being able to play back pre-recorded stereo tapes, so you're right about the 'half track stereo'.
Maybe the two volume controls are used for master and student volumes - you probably need to connect a headset to test that. It would explain the lower level, to avoid deafeing the students!
Just checked that and you're right about that - the second control indeed controls the headset volume! I only tested the output on the 'Free Head'-socket. But that one is obviously a line output. After a second try, the volumes on both line outputs (i.e. on both amps) are equal - no idea why the level was so low last time (probably a bad connection?).

The foot pedal allows 'skipback'.

Unfortunately that is the one thing I can't get to work. Start/Stop works fine now, but 'recap' stops the right reel while the left one keeps feeding tape…not good. Will have to take a closer look at that sometime. Some caps looked like they might need replacement…

Another question: The belts have been replaced now and everything works fine now. But in playback mode the whole thing is still rather noisy. I traced that down to the idler wheel - obviously the machine was stored for years with the control in 'play' position and hence both the idler wheel and the pinch roller have dents from the pressure. They are no longer round and therefore are noisy at higher speeds. Is there anything that can be done about that?

P.S.: I was really impressed with the build quality and the design of this deck. Was the first Tandberg I ever had…..to cut a long story short: I am now also the proud owner of a TR-22O amp and a 3500X 4-track recorder. *grin*

[eclectiktronik]

Unfortunately that is the one thing I can't get to work. Start/Stop works fine now, but 'recap' stops the right reel while the left one keeps feeding tape…not good. Will have to take a closer look at that sometime. Some caps looked like they might need replacement…

You need to observe what actually happens in this mode. My guess is that two separate actions need to happen:

-The pause solenoid pulls the pinch roller away from the capstan (seems the main problem here if you say it still feeds tape!)
-Another solenoid shifts the drive from the take up spool to the supply spool, activating rewind. My guess here is that the drive idler is shifted slightly away from the TU spool (seems to happen OK in your case!) and the supply spool is connected to the belt drive for rewind, probably by moving up the discs/clutch underneath.

I think dried lubrication or dirty relay contacts are more likely to be the reason it is not working.



Another question: The belts have been replaced now and everything works fine now. But in playback mode the whole thing is still rather noisy. I traced that down to the idler wheel - obviously the machine was stored for years with the control in 'play' position and hence both the idler wheel and the pinch roller have dents from the pressure. They are no longer round and therefore are noisy at higher speeds. Is there anything that can be done about that?

Very common sadly -seen this recently too!
I usually use fine sandpaper from a DIY/hardware store. Remove the idler from the deck (don't lose the red washers!) and give the edge a good rub, clean it and refit and test.
Be ruthless, the exact circumference is not critical so take off the hardened outer layer. If it is really bad all the way down, you will need to change it. I know a couple of other tricks but try that first.

Sometimes if you are lucky, a dented tyre/roller will actally regain much of its former springiness if left alone. However, a dented pinch roller will cause bad flutter and should probably be changed.
hope that helps!
Ben

[jdurbin1]

Critical may not be the word for it, but if you change the circumference of the idler you will change the rotating speed of the capstan.

I may have some NOS idlers for this machine; I know I have a few idlers, just not sure which deck they're for other than a 64X one that I am holding onto for my own deck. Drop me a PM if you want, I will do a part number check & let you know.

Idlers can be rebuilt with new rubber also. Terry should be able to do that...

John

[tandberg]

I've sanded lots of idler wheels. I uses a lathe though.
It does not change the speed.
The speed depends of the motorwheels diametre. If the idler got a smaller diametre it will spin quicker (rpm) and the peripheral speed will be constant.

A common misunderstanding.

Of course if the diametre is very much reduced, you'll loose spring tension and 'grip' .

[jdurbin1]

Thanks, that's good to know...

John

[OUTLABIN]

Hi

I have for sale a Tandberg series 15 SL its in very good condition & fully functions its been in storage now for over 12 years unused and before that was owned by a friend of mine a old school teacher who hardly used it himself.

The history... it was one of two spares out of 14 bought for the school and was given to him when he retierd.He told me it was never used at the school and only stored as a spare unit in case in need.

The unit was given to me as payment for a project to record 20 + reels then digital restore them since then it has not been used for over 12 years.

So its up for sale and i would like it to go to a good home.

Im about to list on ebay but i thought would be nice to offer it a round to people who would appreciate it more than some random ebay user who just wants a reel to reel that could end the death of it who knows.

So can you pass this round to see if you know anybody thats interested

*reelspin* *reelspin*

Any offers welcome.

Kind Regards outie