Sony TC-366 won't stay in play mode

[ms660]

Originally Posted by Keith956

In the service manual it says to loosen a screw to locate the idler arm pin between the two slots in the plastic cam. The only screw I can think that might do it is the one that secures the plastic cam to the speed selector shaft, which is completely inaccessible. The photo in the service manual (Fig 11-13) is not clear alas.

6th photo?:

https://www.berlin-repariert.de/sony...y-haelt-nicht/

Lawrence.

[DMcMahon]

Good link Lawrence.

David

[DMcMahon]

Originally Posted by Keith956

In the service manual it says to loosen a screw to locate the idler arm pin between the two slots in the plastic cam. The only screw I can think that might do it is the one that secures the plastic cam to the speed selector shaft, which is completely inaccessible. The photo in the service manual (Fig 11-13) is not clear alas.

Maybe not identical but on page 9 of the TC-399 Service manual there is a better drawing showing this.

David

[DMcMahon]

Old TC-399 photo showing the adjustment screw in the slotted hole, with this screw loose the complete speed change control will rotate I think.

David

[Keith956]

Do you mean this one, circled?

[DMcMahon]

Yes.

[Keith956]

Success! Thank you Lawrence and David.

I unscrewed that screw completely, which let the switch come out. Then found that shaft with the spring that the cam operates was gunked up with solid grease. A bit of IPA and oil freed that, lined up the cam and put the switch back on and hey presto, 3 speeds now!

That German web page is very useful for comparing what things should look like. Need to figure out how to secure the VU meters next, the previous owner has stuck them in with bluetac!

[DMcMahon]

That is good.

Did you set the position of the cam as per the 11-13 procedure ? which says to adjust the cam so that the idler pin is in the middle of the 2 slots in FWD mode, this does not appear to make sense to me and is different from the 399 procedure.

The 399 procedure says to adjust the cam position so that the idler pin drops into the slot. This makes sense as it then interlocks the speed control from being turned if in FWD or FFD or RWD mode. On the 399 at 9.5cm the idler pin drops into the second slot and at 4.8cm the idler pin drops off behind the end of the cam, so also stopping the speed control switch from being turned.

David

[DMcMahon]

Originally Posted by Keith956

There's a hole near the selector knob through which you can see the adjuster screw; to gain access to it there's a slot in the side of the mechanism. Sony must have thought this would need adjusting with the mechanism in place.

Can now see the viewing hole and adjusting slot in the TC-399, seems quite akward to get a small screwdriver into the adjusting screw because the VU meter cutout metalwork is higher and somewhat fouls the screwdriver.

David

[ms660]

Speed selector cam....The TC-266 manual shoes the screw and the pin slots in the manual (Section 8-6)

vintageshifi for my copy.

Lawrence.

[Keith956]

Hi David,

No I didn't follow what it said in the service manual, it didn't seem to make sense. I believe I've set it in the same position as you by trial and error.

The plastic cam has 3 level bits and I assume these are the resting places for each speed for the spring shaft the cam is pressing on. The pictures show the speed selector in 7 1/2, 3 3/4 and 1 7/8 positions. For the slowest speed the shaft with the spring is pressed in the most and the pin is not in line with any slot, for the faster speeds the pin aligns with one of the two slots. It seems to be moving the idler wheel to give the 3 speeds just by looking at the rotation of the pinch wheel during play but I've not tried putting a tape on it yet.

[DMcMahon]

The TC-266 manual has the same reference as the TC-366 about adjusting the cam so that the idler pin is central to the 2 slots which doe not appear logical. The cam is the same part number on the 266, 366 & 399 so would expect the 399 procedure to be also valid for the 266/366.

David

[DMcMahon]

Originally Posted by Keith956

The plastic cam has 3 level bits and I assume these are the resting places for each speed for the spring shaft the cam is pressing on. The pictures show the speed selector in 7 1/2, 3 3/4 and 1 7/8 positions. For the slowest speed the shaft with the spring is pressed in the most and the pin is not in line with any slot, for the faster speeds the pin aligns with one of the two slots. It seems to be moving the idler wheel to give the 3 speeds just by looking at the rotation of the pinch wheel during play but I've not tried putting a tape on it yet.

From the description and photos all looks correct to me.

David

[wave solder]

I've just resurrected my Sony TC-366 too, while you are in there is is a good idea to replace the motor run capacitor before it causes any problems or motor damage, it's 2uF for use in the UK at >250v WKG.

[DMcMahon]

If you do replace the Run capacitor (I am not saying you should at this stage) then make sure it is AC voltage rated and for continous use, most modern run capacitors will be Polypropylene.

[wave solder]

The run capacitor is a known problem in these units, mine only lasted for about an hour after it's rude awakening and the tape slowed right down to a crawl. The bulging top of the capacitor gave the game away. The motor runs on 100V tapped off the main transformer.

[DMcMahon]

Originally Posted by Keith956

There are a couple more issues though. Firstly the brake for the supply spool seems to touch the drive belt when in rewind (see first picture). It might be nothing but that doesn't seem quite right?

Got one of my TC-399s down for comparison. The Supply brake gets close but does not touch the belt in rewind.

David

[DMcMahon]

Checked another TC-399 and on this one the Supply brake does lightly contact the belt.

[Keith956]

I think mine is no worse than yours. Perhaps the rumbling noise on rewind is something else!

[DMcMahon]

Because the reason my one was touching the belt was because the Supply reel table top section was not fitted, when I tested rewind and said it was not noisy, this was with no tape loaded/running.

Yes I think a rumbling sound is most likely something else.

David