UK Vintage Radio Repair and Restoration Discussion Forum

UK Vintage Radio Repair and Restoration Discussion Forum (https://www.vintage-radio.net/forum/index.php)
-   Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players (https://www.vintage-radio.net/forum/forumdisplay.php?f=35)
-   -   Akai 910 reel to reel recorder - valves (https://www.vintage-radio.net/forum/showthread.php?t=128011)

AkaiRick 13th Jul 2016 2:54 pm

Akai 910 reel to reel recorder - valves
 
Hi,
I have an Akai 910 that I've owned from new (1968).
Six years ago I stored it in a shed in Cyprus (not ideal).
When I got it out recently, I found that the amplifier is not working.
The motor and mechanics are perfect but no sound. Apart from normal tape operation not working, I tested the Line In and Line Out functions and it's all dead.
I suspect that a valve/s may have failed.
The amplifier is the same as the other vintage Akai machines, M10, etc..
I'd appreciate any advice as to where I could get the valves tested and replaced, if necessary.
I'm in Westbury, Wilts

Station X 13th Jul 2016 3:39 pm

Re: Akai 910 reel to reel recorder - valves
 
I'd say the problem is unlikely to be valve failure and replacing them or even getting them tested would be a waste of time and/or money.

First thing to check is whether the valves light up. If not they're unlikely to be all blown unless the recorder has been connected to the wrong supply voltage. It's easy to check heater for continuity using a DMM.

You should also check LT and HT voltages.

Station X 13th Jul 2016 4:01 pm

Re: Akai 910 reel to reel recorder - valves
 
I've just looked at the Akai M10 manual and it's all transistor ie no valves. Are we at cross purposes here?

AkaiRick 13th Jul 2016 4:22 pm

Re: Akai 910 reel to reel recorder - valves
 
Thanks Graham.
The valves all light up.
Rick

AkaiRick 13th Jul 2016 4:24 pm

Re: Akai 910 reel to reel recorder - valves
 
Goofed again!
Thanks

AkaiRick 13th Jul 2016 4:29 pm

Re: Akai 910 reel to reel recorder - valves
 
M-8. Two amplifiers on top of each other.
I think all Akai valve recorders were the same or similar.

Station X 13th Jul 2016 4:42 pm

Re: Akai 910 reel to reel recorder - valves
 
If ALL the valves light up, including the rectifier, then all LT supplies are present.

The next thing to do is check for HT voltage across C25.

Circuit here:-

http://audiokarma.org/forums/index.p...t-down.460792/

AkaiRick 16th Jul 2016 12:06 pm

Re: Akai 910 reel to reel recorder - valves
 
Thank you everyone. I shall use your expert advice when I'm next united with my 910.

So glad I joined!


All times are GMT +1. The time now is 12:56 pm.

Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.