hifi engine

Manual Library / Sony

Sony TC-377

Stereo Open Reel Tape Recorder (1973-77)

add a review add a review

Sony TC-377


The Sony model TC-377 is a three-head, four-track stereo tape deck designed for serious home recordists.

The highly developed facilities of the TC-377 will offer a new world of sound when used in conjunction with quality high fidelity components.

Special features include high performance Ferrite and Ferrite heads, microphone level attenuation switch, scrape filter which eliminates tape modulation distortion, tape tension regulator to reduce wow and flutter, automatic shut-off mechanism, tape select switch for low-noise high-output tapes, microphone and line mixing, sound on sound recording, echo recording, slant cabinet designed for convenience of operation in either horizontal or vertical position, etc.

In addition to these professional features, the model TC-377 is also designed to record and play back encoded SQ (Stereo Quadraphonic) signals with true fidelity.


Track system: 4-track, 2-channel, stereo/monaural system

Heads: 1 x record, 1 x playback, 1 x erase

Motor: 1 x induction motor

Reel size: up to 7 inch reel

Tape speeds: 1 78  3 34  7 12 ips

Wow and flutter: 0.09% (7 12 ips)

Frequency response: 20Hz to 30kHz (7 12 ips)

Signal to Noise Ratio: 55dB

Total harmonic distortion: 1.2%

Input: 60mV (line), 0.2mV (mic)

Output: 0.775V (line)

Semiconductors: 23 x transistors, 5 x diodes

Dimensions: 418 x 210 x 392mm

Weight: 10.6kg

Accessories: empty reel, RK-74 connecting cord, motor pulley, head cleaning tips


Related Catalogues


HiFi Stereo Quadro


Technology Of The Future

If you have any problems opening files please read the download FAQ. All files are provided under strict licence and reproduction without prior permission or for financial gain is strictly prohibited.

If you have additional documentation please consider donating a copy to our free archive.


re: TC-377


just serviced my TC 377 with the aid of excellent videos on YouTube.

Used Superlube grease (bought on eBay) plus fitted new belts.

The machine was running very slow @ 71/2 but with the help of this forum managed to correct problem, i.e thoroughly cleaned and greased / oiled all moving parts, particularly the Idler, and as recommended in the forum shortened the Idler spring.

So far so good all working fine.

Trust the above helps someone out, Cheers Alan R

re: TC-377 60 hz pulley needed

does anyone have a 60hz pulley my tc-377 has a 50hz so it plays to fast

re: TC-377 60 hz pulley needed

Hi, sorry my reply isn't about the pulley you have been asking for. I'm currently finishing up restoring a wonderful piece of sony tc 377 and i got the front light 2 wires disconnected by mistake. i tried to find my way through the service manual to be able to connect them back again to the connection bar behind the vu meters but I couldn't find it.
If you have the machine open can you guide me please with a photo to the connection bar behind the vu meters.

Would really appreciate your help. and good luck with your restoration job.


re: TC-377 60 hz pulley needed

Is your unit made for 50hz use only?
I also call it that the motor is 50hz and that is what needs changing out.

re: TC-377

Has anyone done any work on the amplifier boards? It appears one side is not working properly and I'm wondering if anyone has retrofitted the board or found used ones?


re: TC-377

Mikey, I just found this site and your message. Did you ever get the solution? I have been refurbishing the 366 & 377, selling on ebay, over 60 so far.....I have six now that have the same problem. I find tracing the signal to where it gets lost and replacing that part is the only answer.

re: TC-377


I have a 377 and it won't stay engaged into rewind/ff or play (otherwise it plays pefectly)

I have replaced a spring that was very worn on the plate below the head block and regreased all moving parts but I still have the same problem.

I was wondering if you have any ideas or a replacement panel that the head block bolts onto?

Or perhaps repair it for me?

I'm so sorry I can't explain in more detail but I'm new to all this because I'm no engineer.

I have taken my time and replaced all screws /parts as they were removed.

Look forward to hearing from you and happy new year.

Best wishes,

re: TC-377

The is an adjustment screw for it under the front of the head block . if you lay the backing on its back and look down on to the head block , you can see a spring and thats the screw . You access it buy putting a philips under the gap between the head block and the chassis .

Its more likely though that the mech spring has flipped the wrong side , I repair this daily almost .

All the best

re: TC-377 slow runing when vertical only

Anyone have an idea what to check for TC377 slow running in 7.5ips in vertical position only (works fine when horizontal). So far have lubricated the motor and cleaned the idler wheel with no improvement. I'm thinking idler wheel tension; but can't find a way to check/adjust it?

re: TC-377 slow runing when vertical only

Idler wheel needs rebuilding. Rubber has gone hard on you.

re: TC-377 slow runing when vertical only

There's a small spring on the arm that holds the idler, I cut this spring shorter and bend the cut end into a hook and re-attatch it and this has always worked for me
Good luck with it Gordon

re: TC-377 slow runing when vertical only

I just found you lot today, my 77 TC377 came out of retirement last week after too many years, nearly all working good after a bit of a clean up. It does run slow at all speed vert or horizontal, I will try spring on idler to see if fixes else i will be back thank you. Bruce

re: TC-377 slow runing when vertical only

Need to remove all of the old hard grease and relube with Lubriplate.
Capstan Idler wheel needs to come off, shaft and wheel axle cleaned with solvent and light oil and reinstall.

re: TC-377 slow runing when vertical only

Unfortunately not only what it shows in the service manual.

re: TC-377 Belts

Just found this site and very excited. I need new belts for my recorder, where can I find these?

TC-377 take-up reel problem

Hello all, I hope someone can help. My deck's take-up reel suddenly stopped turning in Play. It will turn in Fast-Forward. Where should I look first, and is this somethingI can do, or should I take it somewhere? Thanks!

re: TC-377 take-up reel problem

Broken or loose belt from the capstan to the right reel.


re: TC-377

Hi everyone. I hope that you can help me with three parts that I need for this model. They are all for the take-up reel. One is the reel's internal spring and the screw thing it goes over.The third item is the external screw that holds them in place. These are all accessed from the top of the machine. No cover or anything to remove.Plus these parts are interchangeable with the same parts on the supply reel.
Another thing that I would like to mention is the fact that the machine does not record and therefore playback a signal above approximately 9KHZ at the slowest speed. I have tried a half dozen different tapes with no luck. 3-3/4 is OK and of course 7-1/2 is good. But 1-7/8 speed does not reproduce anything above that frequency. Is this normal? I have only recently acquired this machine. That speed-1-7/8 does record and playback OK but since it is of such poor fidelity-I don't really want the machine. I am in Oshawa, Ontario. Thanks. Len.

re: TC-377

You can buy the complete reel table ass'y on ebay. I think I have one for sale.
Yes, 1 7/8 is bad for audio, it was designed for speech / voice recordings only.

re: TC-377

I appreciate your feedback. Thanks. Len.

re: TC-377

It's a bit late to respond to the problem of the function FW RW PLAY, not staying locked in, but…..I had this problem and followed this person's advice on you tube. Worked great, You wouldn't think so but the area that needed cleaned was a small cam/bushing beneath the selector knob. In order to do it you will need to remove the four screws that hold the head assembly and turn it up side down to see the area. You do not have to remove the entire head assembly, wires and all. Just undo a few linkages and turn it upside down and tuck a cloth underneath to protect from overspray.

re: TC-377

Hello to everyone,
I have an original TC 377 sony reel to reel it works verywell but after playing some tapes suddenly the speed goes waydown,and singers voice sounds like an oldman ,
does this cause because of old dirty tapes,and what is the best cleaning solution for pinch roller and tape paths
thanks for any help

re: TC-377

Switched mine on for the first time in a long time, something went pop, maybe a capacitor In the power supply? Any ideas

re: TC-377

Mine did this as well. It was the supression capacitor across the mains. Easy repair.

re: TC-377

Reels turn very slow in forward position & do not turn in rewind position. Turned reels by hand: ake-up reel seems to turn freely, other reel (left side) seems to turn very hard. Belts are in place and seem to be working. Any solutions?

TC-377 Function Control Knob does not stay in place

This machine has not been used for a long time and I find the the main function control knob no longer locks in place in rewind, fast forward and even in Play it really doesn't lock in solidly. I've lubed all the linkages and cams on the main function control but this doesn't seem to help.

Anyone else have this problem and perhaps have a fix for it?


Function control does not lock

Hi fesnell.

You're in luck, as i just logged-in for the first time in about 2 years to get a copy of the service manual for a TC-377!

OK I have two of these units and one has had this same issue. Are you at all mechanicaly minded to work on it yourself? I've found the problem to be a tiny little return spring wrapped around a little metal stop-block thing that's part of the auto-stop feature lever at the back of the function control knob mechanism. It for some reason tends to slip out of place(unwraps itself). IT kind of puts the unit into perminant auto-stop mode as though you have left the lever down. There is also an adjustment for the sensitivty of the auto-stop(It should be in the service manual). You'll have to remove the plate which holds the heads etc to get to it all. Don't remove the head block from this plate if you can avoid it so as not to need to re-align the entire record/play heads etc.

Anyway you'll find it when you get there, good luck!

Sony TC-377

The reels aren't turning. Can anyone help?

Sony TC-377

I've just looked at one of these for a friend of mine. Check your drive belts and drive surfaces first.
The problem I had was that the control could not be moved to the play position. This was due to the pinch roller mounting pillar jamming, this was easily cured by regreasing the mounting. Check also the cam that drives the roller from underneath.



I just bought a used Sony TC-377 and only two speeds, 3 3/4 and 7 1/2, will turn. The other speed 1 7/8 refuses to turn the spool. Can any one tell me what am I looking at needing to do to remedy this.


Its either the rubber on the drive idler gone a bit hard or the spring which pulls the idler in contact with the flywheel & motor stretched slightly . I have a 377 which does this and if I force the idler harder into the motor etc it works ok. Im looking to start making a replacement nylon idler with a new drive tyre when I can get a small lathe.

Sony TC366

Anyone have the manual for this model?

tc 366 manual

The service manual for tc 377 should suffice. There were only minor changes from the 366 to the 377.

manual for TC-366

I actually have the original manual for this tape deck. I also have the tape deck that I purchased new back in the 70's. I could copy this for you if you are still interested.

user manual tc-366

Yes, I really appreciate if you would douwnload a copy of the Sony Tc-366 manual for me.
Thank you ,Phil G

My Sony TC-355 is running fast

Any chance someone knows how to adjust spped?

tc-355 running fast

Dear sir,
Pleaase see the pinch roller tension.if it is ok then check the drive belt
whether it is gone loose.if the belt is loose it will give u the speed problem.

This website is not affiliated with or sponsored by Sony. To purchase TC-377 spares or accessories, please contact the company via their website or visit an authorised retailer.