Late 60's hybrid amp filament question

BiBi · 10-10-2009, 05:42 PM

I just picked up a cheap no name amp-- I think it's Italian-- that is apparently from the late 60's to early 70's. It uses two el84s and a transistor front end and Pi. It's in bad condition all around but the transformers luckily are intact.
The question I have relates to rebuilding the amp with all valves.
The power transformer is quite bulky and has a marking TA140MA. I'd take that to mean 140 mA although I'm not so sure. The other problem is the filament winding- is there enough current to supply one to two more tubes? How does one calculate the current from a given transformer?
Thanks for any help

Giaime · 10-22-2009, 01:09 PM

If it can help you, "TA" is the popular acronym in italian for trasformatore d'alimentazione, or power transformer.

BiBi · 10-22-2009, 01:30 PM

Grazie! I found out a bit more of this amp-- it's a Gem produced model for Galanti. I installed a new small transformer for preamp heater valves and presto the amp came to life. It was a bass amp originally with a large ampeg portaflex style cabinet. What a great sound!

10-10-2009, 05:42 PM	#1
BiBi Junior Member Join Date: Sep 2009 Posts: 5	Late 60's hybrid amp filament question I just picked up a cheap no name amp-- I think it's Italian-- that is apparently from the late 60's to early 70's. It uses two el84s and a transistor front end and Pi. It's in bad condition all around but the transformers luckily are intact. The question I have relates to rebuilding the amp with all valves. The power transformer is quite bulky and has a marking TA140MA. I'd take that to mean 140 mA although I'm not so sure. The other problem is the filament winding- is there enough current to supply one to two more tubes? How does one calculate the current from a given transformer? Thanks for any help Last edited by BiBi; 10-10-2009 at 07:56 PM. Reason: unclear what I wanted answered

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10-22-2009, 01:09 PM	#2
Giaime Junior Member Join Date: Oct 2009 Location: Venice, Italy Posts: 1	If it can help you, "TA" is the popular acronym in italian for trasformatore d'alimentazione, or power transformer.

10-22-2009, 01:30 PM	#3
BiBi Junior Member Join Date: Sep 2009 Posts: 5	Grazie! I found out a bit more of this amp-- it's a Gem produced model for Galanti. I installed a new small transformer for preamp heater valves and presto the amp came to life. It was a bass amp originally with a large ampeg portaflex style cabinet. What a great sound!

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