Mitsubishi VCR Repair

[Outland]

I'm working on a Mitsubishi HS-U51.



This is the left spool. What is that belt? It is loose, and it isn't clear where it's supposed to be.

It can also be somewhat seen on the studio sound electronics page.

[Ed in Tx]

Not a belt, a back-tension band that adds a controlled tension on the tape. It's supposed to be loose in eject mode. It engages when the machine is in play-record, controlled by the back tension arm that rides on the tape and a tension spring.

[Outland]

Got it. Thanks.

[Ed in Tx]

Be sure to read my edited version.

I had to re-read and look closer at your pic before I finally got it right and did a few edits.

Sometimes the back tension band fails, the felt lining comes unglued and falls down in the mechanism, but that one looks good.

Check the belt on the bottom of the deck, commonly failed, stretched or turned to goo. If that slips or is no good it won't front load the tape.

[Outland]

Yeah, the belt on the bottom is completely loose. The motor spins by itself. I'll replace it with a belt from studio sound electronics.

Looks like a nice deck.

[Ed in Tx]

Yep those were nice decks. I have a HS-U52 here I've kept in operable condition. Similar mechanism. Another problem was the plastic pulley pressed on the capstan motor. It would crack and slip, and then no go. They used to sell a brass pulley kit to fix that.

Capacitors like to fail in these too. Sometimes you can see discolored blackened foil traces on the top of the board from the leaky cap underneath.

That's the problem with 25 year old VCRs.

[centralradio]

I had a couple of Mitsubishi's here one was a HS-U48 and a SVHS model which I cant recall the model number at this moment.All bought new. They did not last here as the capstan motors fried on both of them since i do alot of tape shuttling and they had a habit of bad solder joints.Basically they fell into the same dept as the NEC's I had here.They were great to use but they dont last. I has the pulley coming off the capstan here too.I just super glued it back on.

[Ed in Tx]

HS-U48 is a completely different mechanism and overall build compared to the HS-U51.

[centralradio]

Originally Posted by Ed in Tx

HS-U48 is a completely different mechanism and overall build compared to the HS-U51.

OK thanks .

[Outland]

No leaky caps as far as I can see.

I ordered a new belt and we will see how it behaves.

[Outland]

New problem. Belts are now good, but VCR does this (click for vid).

The tape doesn't get caught by the guides and doesn't get pushed against the drum.



??

[Ed in Tx]

You zoom in just as it loads, and I can't see what the reels are doing. Looks like maybe the brake on one or both reels isn't releasing. Not very good on the tape!

[Outland]

Good call. Let me post another video.

That's a sacrificial tape. It has seen much worse.

[Outland]

Here it is.

[Ed in Tx]

I sure don't like the ratchet sound it makes. Is the post there on the deck that pushes the cassette's brake release?

I think when one of these loads the TU reel stays fairly stationary so it comes up roughly the same place on the tape when ejected. The Supply side should go free to fed the tape with just a bit of tension from a soft brake to keep a little tension on the tape as it loads.


Do you have a "dummy" test cassette, one with no tape or reels and the windows cut out so you can see better and feel what's going on? With that you could pull the plug just as the TU and Supply arms start their move, to check things like what the reels and brakes are doing at that point. Also handy in fully loaded play position then unplug you can at least see if the back tension arm and band are working OK. I used to replace a lot of back-tension bands, and reel brake arms too, the black pads on them wear out.