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Reading 38-116 Tube Pin Voltages with Tubes Horizontal
#1

I'd like to record voltages for tube pins in the 38-116 Code 125 I've been working on. After testing tubes, re-capping, and replacing out of tolerance resistors, the radio plays with distorted audio. I can set the chassis upright on the end with the power transformer, secured to a lazy susan turntable. I also have support under the edge of the power transformer so the corner 6L6G tube doesn't touch the turntable. Is there any issue with operating these tubes in a horizontal position? The tube lineup is 6U7G 6A8G 6A8G 6N7G 6K7G 6K7G 6J5G 6K7G 6J5G 6R7G 6J5G 6L6G 6L6G 5X4G; except mine has a 5Y4G in place of the 5X4G.

Thanks,
Larry


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#2

Not a good idea especially for power tubes and rectifiers. Supposedly you can negate the possibility of a short caused by sag by positioning the tube (rectifier) just right, unfortunately they did not build the chassis with this consideration. Short term - maybe. Long term - No.

Upside down should be OK.

P.S. Old Suckers might have trouble reading your posts - increase your font size.

"I just might turn into smoke, but I feel fine"
http://www.russoldradios.com/
#3

Thank you, Russ!  I've seen photos of the nice chassis fixtures that some have built to allow rotation to inverted.  Building one of those would be a challenge for me; I was hoping to get away with a less distinguished approach.
#4

Tubes are OK to operate horizontal for limited time. Which is long enough for troubleshooting. Hours are OK. Even days.
After all, some old radios (abeit few) with older tube types were built with tubes horizontal.

So let's just say, for your purposes (troubleshooting) it is ok.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#5

OK, thanks!  It would just be for troubleshooting.




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