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Old 06-28-2017, 05:43 PM
Mike52787 Mike52787 is offline
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Broken, Please help!: Sencore Super Mack

Hey, I recently picked up a super mack from a local store for $20, and it seems to be broken. Thankfully, I received all the tips, with a few extras, and a setup chart. However, when I turn it on, and turn up the filament voltage, the meter displays nothing. no matter what I do it seems to be dead. the light comes on on the side it is switched to, and it seems to power up, however I do not want to plug it into my TV without a readout on the filament voltage in the odd event it would destroy the quite nice picture tube in it. I am a relative novice with test equipment, and would love to get this working. I have not opened it up yet either. just looking to get more info on hopefully fixing it first. Thanks in advance for any info.
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Old 06-28-2017, 06:26 PM
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Notimetolooz Notimetolooz is offline
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I don't know that tester, I guess it a CRT tester, it may be a problem with the meter circuit. I that case it could be putting out a higher voltage than you would want to put on the CRT. That wouldn't be an 'odd event', its a real possibility. Do you have a voltmeter you can use to check the voltage at the CRT socket?
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Old 06-28-2017, 08:09 PM
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N2IXK N2IXK is offline
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Check for filament voltage between pins 1 and 11 on the 11 pin adapter cable.

If present, suspect a problem in the metering circuit.

If not present, look for a fault in the filament transformer, filament selector switch, life test switch, or filament set pot and associated 15K resistor.

The "CRT Test" and "Beam Builder" lights are fed from a separate transformer than the CRT filament.
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Old 07-08-2017, 11:18 PM
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Tubejunke Tubejunke is offline
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Quote:
Originally Posted by Mike52787 View Post
I am a relative novice with test equipment, and would love to get this working.
I feel pretty well versed with at least vintage test equipment as well as some of the modern stuff, but by description it took me a while to figure out what we were talking about. As I scroll the thread it becomes safe to say that it's a standalone CRT tester, and/or rejuvenator. I really haven't heard of the Sencore Super Mack.

Sounds like you got some pretty good advice for starters at least, AND you seem to be a good logical thinker, which can produce a good troubleshooter and not a trouble causer. LOL! The best advice I can give you is to say that when you are seeking help on a topic forum, always provide the name AND the model number. But equally important (as I learned) these days is that many people wont respond that may have valuable info. if you don't post a picture of the unit, or a few if you wish. Just offering Super Mack as all of the description limits you and the WWW from tuning into what you have.

The biggest reason is that most equipment manufacturers didn't have a new pet name for one kind of tester every year. The Super Mack could have been made for a decade or two. Simpson has been making the same "260" analog volt ohm meter (VOM) since I think the 40s! LOL! And they still make shiny new ones today that APPEAR to be the same thing, but MANY internal changes have taken place through all the years.

Not trying to preach, but rather to teach here because specific information can and will make or break you in electronics. Without that you can't even swap tubes......
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Old 07-08-2017, 11:52 PM
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jr_tech jr_tech is offline
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There is a troubleshooting guide in the manual:

http://www.oldtubes.net/library/test...r31a/CR31A.pdf

jr
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Old 07-10-2017, 04:24 PM
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Notimetolooz Notimetolooz is offline
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I guess the meter on 'Line Volts' doesn't show anything either, normally that's where setting up to test a tube would start. N2IXK is right about checking for filament voltage on the CRT connector. You could also try connecting a 6 volt lamp like a # 47 across those pins and setting the filament selector to 6.3V. I wish the manual showed a complete schematic. Try to get the filament supply circuit to work first, then go on the the other sections. I would guess that it is in the meter circuit somewhere, the meter itself or the switches. The manual doesn't show a fuse in that circuit but there might be one.
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