Project 1970s Rediffusion Reditune TP80

Wow! An hour later, I get a call, they've done it! Windings rotated, new hole drilled in top house for lead-outs. Anyone local, I highly recommend these guys, both retired and only keep the business open because they enjoy what they do. I imaging it will be gone in not so many years from now.

Happy days.

This has now revealed a couple of things to me.

The original TP80 motor was 1400RPM, the replacement also 1400RPM. I now know that the TP80 runs at the same speed as the TP48. How do I know? Trying to play the large red carts, reveals the music is too slow. Putting in the smaller TP48 carts, the music runs at the correct speed.

I can only guess that the Red carts might be for the TP80S, a clue perhaps is the cart's state Stereo. The TP80S was the stereo version of the TP80, maybe the speed was increased on that version, meaning the stereo carts are not backward compatible.

The motor appears to be unstable, as the wow & flutter is phenomenal, making the music reproduction awful. Not sure why this is the case, perhaps the belt has stretched.

I'm quite amazed the TP48, as hideous as it initially looked, has turned out to be the more viable restoration than the TP80. The TP48 is happily running, this TP80 is turning out to be a money pit. I'm going to park this one for a while now and come back later in the year, after all I have the TP48 working, and a working system was what I wanted. I also want to get back to the 4Ks as I've spent far too much time on these Reditune's.

Is the motor casing bolted directly to the chassis? Ideally it should have some rubber isolating bumpers, it may be that vibration from the motor may be being induced into the chassis. Just a thought.

Posted by: @jayceebee

Is the motor casing bolted directly to the chassis?

Yes it as, and I had little choice as the motor is so much bigger than the original one, every millimetre counted. This was the only way to shoehorn it into the case and have the pulley align with the capstan flywheel. As it was, I still had to cut away some of the chassis to allow part of the motor housing to protrude by about 5mm.

I think I need to find a 1400RPM motor that is nearer to the original in size, but that's not going to be easy. Besides, as intimated above, I've been working on these reditune's since Jan. Time to have a break and get back to the telly's, those 4K's are giving me sour looks for having left them in pieces for so long. 😉 

I'm still happy to send you a Collaro tape deck motor to experiment with, Chris but equally, I want to see what these 4000s look like on screen!

Hi Mike, well I'd certainly like to give it a try, I hate been beaten.

Do you know the dimensions of the Collaro motor, the closer it is to the original the better. The replacement was the right diameter, but far greater in height than the 45mm, of the old. That caused me grief and resulted in my inability to use rubber mounts, the spindle only just aligns for the capstan belt. If the Collaro is much larger, I will face similar problems. Also, if it's the wrong speed, I've no idea or ability, to know how to address that.

Having said all that, If there's a slim chance it can be made to work, I'm happy to give it a try, and cover all costs getting it here.

p.s.

Re the 4k's, me too, getting back in the saddle on those tomorrow.