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Thanks, Bill!  A step at a time.  Gloriously Complicated.   ;) :)
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Magnificent Magnavox / Re: Magnavox Stereo Theater 1MR418M restoration
« Last post by Bill on Today at 06:59:08 PM »
I'm impressed!  It looks very neat and tidy.  :) 

Bill
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Electronics / Re: What's the correct procedure for Variac use...
« Last post by electra225 on Today at 04:51:03 PM »
Clock motors and record player motors are not happy much below 110 volts.  TV guys don't like using a Variac on certain TV models (don't ask me which ones!) because the horizontal oscillator will not run, thereby possibly damaging the flyback and other parts in the high voltage section.  There is a famous YouTube channel that does not use a Variac much if at all.  Just plugs them in and monitors wattage.  I worked on radios for almost 20 years before I had a Variac. 



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Electronics / Re: What's the correct procedure for Variac use...
« Last post by firedome on Today at 03:20:05 PM »
I know what they are and do, had one and been using it for 30 years, but I've heard in the past by some knowledgeable folks that starting at too low a V can be harmful to certain tubes or other components, raising V too fast can be harmful, yada yada and I prefer to go by facts, so while I've never had a problem I've long wondered what the reasons are for those statements as I said by some very knowledgeable people ie: EE types. I should have questioned them at the time but didn't.
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I have had the privilege of communicating with the Magnavox guru, whose identity shall remain top secret for the moment.  I have also found a NOS diode assembly should that become a necessity.  There are three different configurations of these diode assemblies, determined by schematic diagram and part number. The advice is to forge ahead like I knew what I was doing and, that should I have a sync problem sometime in the future, we could work thru that with no problem.  I'm sure learning a lot.


I have some pictures of the damper socket I replaced.  I used #4 stainless bolts and nuts.  I put some little rubber caps on the ends of the bolts, allegedly to prevent arcing, but mostly because I did not know any better.  They don't make tube sockets the same size.  The holes are different, the bolt locations are different.  Why could not sockets be made the same in all dimensions?  I had to get creative to make it work.  I removed the terminals from #1,2,4,6.  I only needed # 3,5,7,8. 


Most of you guys are not impressed with changing a tube socket, but I'm including this so I can document my project.  Thanks for bearing with me.   ;) :)
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Magnificent Magnavox / Re: K600 Turntable, help Identify this needle
« Last post by Bill on Today at 12:39:03 AM »
The reason I recommend replacing the cartridge for your unit is what Greg said.  But, I also have been burned a lot, buying a needle only to find out the cartridge has issues.  My last burn was on my Berkshire.  It had a Shure cartridge. Shure don't go bad, right?  I purchased a new needle, not the problem.  I do admit, I wish it had been just the needle.  I'm not all that impressed with the new cartridge.

Bill
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Magnificent Magnavox / Re: K600 Turntable, help Identify this needle
« Last post by electra225 on March 24, 2019, 10:04:05 PM »
There were no stereo 78's to my knowledge.  78's were pretty much obsolete by the time stereo was introduced.


Go ahead and replace all the caps, resistors, test the tubes, clean controls and make critical adjustments before you assess performance.


The pictures of the cartridge you posted are pretty blurry to may old eyes.  Looks to me like the bridge is totally gone for the LP needle.   There is no place to attach the needle, probably why it's gone.   My advice is to get a new cartridge and be done with it.
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Magnificent Magnavox / Re: K600 Turntable, help Identify this needle
« Last post by Paulie82 on March 24, 2019, 09:52:29 PM »
Couple more shots of the cartridge.

Only identification can find is a 032 printed on the mounting bracket, and what appears to be a 'T' on the side of the cartridge.
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Magnificent Magnavox / Re: K600 Turntable, help Identify this needle
« Last post by Paulie82 on March 24, 2019, 08:33:40 PM »
I do have a set of old 78's records,  doubting they are stereo since its not called out anywhere on record or cover.
Playing the 78,  getting 99% of the sound on the right channel.

When played an LP on the 78 needle ( will stop doing that) & FM seems like the sound level is 60% on right / 40% left channel,
  with the left channel sounding a tiny bit dull when crank the balance all the way. 
Still working my way thru the console, have 4 resistors left to replace in the amp ( amp-196), 2 of those are connected to the balance control, have not replaced the cross-over caps, so not sure if those things are causing the balance issue.

I'll try to get a better picture on the cartridge.


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Electronics / Re: What's the correct procedure for Variac use...
« Last post by electra225 on March 24, 2019, 05:45:20 PM »
I'm not sure there is a published protocol for using a Variac.  All a Variac is is a transformer with an adjustable output.  Its benefits are to isolate the device under test from the AC line and to be able to vary the voltage during power up.  It is also important to have some type of way  to monitor current, amperage, wattage, whatever.  A dim bulb is typically used, is cheap to make and saves many a device from the effects of a short in B+.  A wattmeter is good, too. 


I typically start at 50 volts with the dim bulb in series with the load.  Then after I determine there is no short, I typically increase voltage in 10 volt increments.  There is no right or wrong way as long as you are successful.
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