Agreed on the dim bulb tester. That said, I use an isolation transformer feeding a variance feeding a dim bulb tester for all tube equipment under test. But for a 4 year old device, I’d start with the variance at 100 percent but the dim bulb tester at say 30%. Assumes a multi-bulb unit. Any problems will be obvious in a minute or two. Good luck!
VARIAC: Procedure??? 2 old 30 wpc tube amps, unused for 4 years
Two Fisher 80Z, made 1958, overhauled 6 years ago, not used for 4 years
https://www.hifiengine.com/manual_library/fisher/80-az.shtml
Borrowed my friend’s VARIAC.
How many volts ___ to start?
Progress in ___ Steps?
How much time _____ each step?
.................................................
I found this, but always seek and welcome advice here
https://www.circuitspecialists.com/blog/using-a-variac-to-power-up-an-old-radio-or-amplifier/
says sniff/look for smoke while:
slowly dial up to 50V; 30 mins (pre-heat tubes; reforms electrolytic capacitors)
slowly 75V; 30 mins (power transformer/windings/drives out moisture)
slowly .............. 90V; 30 mins (if hum replace electrolytic capacitors) (old capacitors: replace em anyway).
slowly up to 110/120V
....................................................................
I’m gonna drop my Cayin off to have it’s internal bias adjusted by Steve at VAS
so, a chance to use these beauties (beautiful sound, actually hard lookers) with my McIntosh mx110z for the 1st time.
They will be driving the Electro-Voice speakers they were paired with in the 1958 Fisher President II I inherited. Always gives me good memories of my Uncle Johnny.
He had a fabulous apartment in NYC with one of a matching pair of Steinway Concert Grand Piano’s from the 1934 Chicago Worlds Fair that my Grandfather bought. My Uncle Bill had the other one. Trust Funds for the brothers, but not for my mother or her sister, they were expected to marry well. My aunt married into the Vanderbilt family, not my mother. Hence I’m the DIY bargain hunter.
https://www.hifiengine.com/manual_library/fisher/80-az.shtml
Borrowed my friend’s VARIAC.
How many volts ___ to start?
Progress in ___ Steps?
How much time _____ each step?
.................................................
I found this, but always seek and welcome advice here
https://www.circuitspecialists.com/blog/using-a-variac-to-power-up-an-old-radio-or-amplifier/
says sniff/look for smoke while:
slowly dial up to 50V; 30 mins (pre-heat tubes; reforms electrolytic capacitors)
slowly 75V; 30 mins (power transformer/windings/drives out moisture)
slowly .............. 90V; 30 mins (if hum replace electrolytic capacitors) (old capacitors: replace em anyway).
slowly up to 110/120V
....................................................................
I’m gonna drop my Cayin off to have it’s internal bias adjusted by Steve at VAS
so, a chance to use these beauties (beautiful sound, actually hard lookers) with my McIntosh mx110z for the 1st time.
They will be driving the Electro-Voice speakers they were paired with in the 1958 Fisher President II I inherited. Always gives me good memories of my Uncle Johnny.
He had a fabulous apartment in NYC with one of a matching pair of Steinway Concert Grand Piano’s from the 1934 Chicago Worlds Fair that my Grandfather bought. My Uncle Bill had the other one. Trust Funds for the brothers, but not for my mother or her sister, they were expected to marry well. My aunt married into the Vanderbilt family, not my mother. Hence I’m the DIY bargain hunter.