Otari MX5050 counter issue. Help!

snipeguy

snipeguy

Andy Goldsworthy Wannabe
The counter on my Otari MX5050 8 track does not advance. It shows zeros all the time. I went deep and found the counter unit. (Part # PB9A310) It appears to be a notched wheel (that is attached to the counter roller) that spins through two black plastic pieces that are on a small CB . These pieces have an LED-like clear bulb on each side. There is 4 volts DC going to one side (LED) of each unit and 1.5 volts to the other. I am assumming that as this appears to be an optical counter, one side should light up. Am I wrong here?

Is my counter pooched or can I just replace the LED 's?
 
snipeguy said:
The counter on my Otari MX5050 8 track does not advance. It shows zeros all the time. I went deep and found the counter unit. (Part # PB9A310) It appears to be a notched wheel (that is attached to the counter roller) that spins through two black plastic pieces that are on a small CB . These pieces have an LED-like clear bulb on each side. There is 4 volts DC going to one side (LED) of each unit and 1.5 volts to the other. I am assumming that as this appears to be an optical counter, one side should light up. Am I wrong here?

Is my counter pooched or can I just replace the LED 's?
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I don't know anything about your deck. However the optical unit should be an insdury standard. Yes, one side is a LED and the other is a photo-transistor. The LED may emit inthe infrared so you most likely would not be able to see it. Some video cameras are sensitive to infrared and they may be able to see the LED. You should be able to (using a schematic) find a test point for the counters signal. As the reel is turned the level will toggle between "high" voltage and "low". Typical ttl levels are .2 and 1.4 v.

If you do not get any toggling the phototransistor or LED is the most likely faulty component. Otherwise it is further down the counter chain.

good luck and Merry Christmas!
 
Thanks. I'm going to check it out right now. BTW I have a buddy that tried to summit Acongagua. I think was few thousand feet short before bad weather turned him back.

I'll keep you posted.
 
snipeguy said:
Thanks. I'm going to check it out right now. BTW I have a buddy that tried to summit Acongagua. I think was few thousand feet short before bad weather turned him back.

I'll keep you posted.
Click to expand...

Good luck with the deck.

Acoucagua can kill you very quickly. There are bodies all over the mountain. But it was a good climb. I really enjoyed it.

A summit photo is at: https://homerecording.com/bbs/showthread.php?t=174914

I keep thinking that I need to head off to do Cho Oyu sometime in the next 4 years....
 
Infrared photo interupters work fine. The problem is farther down the chain. Without a schematic I don't think I can do much more. Off to the repair shop.....when I can afford it. :rolleyes:
 
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