Edcor Universal Power Transformer for Tubelab SE

[G]

Originally posted by Wavebourn
Today I've discovered a weak point of an Edcor transformer...

Did you drop it or something?

[Evenharmonics]

Originally posted by G

Did you drop it or something?

Possibly the result of "shaken amp syndrome".

[ethermion]

I hear they have been getting complaints about the optional "installation tool."

[tubelab.com]

Good timing too, as a friend of mine has loaned be a pair of Chinese 300BS tube

I finally got to the warehouse to retrieve another pair of tubes for you to try. I need to go to the post office tomorrow to mail my taxes, I will send them as well.

Did you drop it or something?

There was another thread detailing the treatment of Wavebourns amp by Fedex

[rknize]

Thanks. I just got what I need from AES for those....

[rknize]

One has a rattle, but it appears just to be cement in the base. Thanks again!

The iron should get here on Wednesday, so I'll hopefully post test results by the end of the week. Looking forward to putting C4 in so I can cut the hum.

[rknize]

Here it is.



Wire coloring leaves a few things to be desired, but it seems to work as expected.



Voltages came in a bit high, even under load. The top row is the Tubelab SE in "45 mode", with about 25mA per tube. Meters are reading: 660VAC winding, 520VAC winding, B+ at the filter cap. Bottom row is in "300B mode", running Shuguang 300Bs (not mine) at about 28mA per tube. First two meters got swapped: 520VAC winding, 660VAC winding, B+.



The B+ in "45 mode" is a bit higher than I was hoping, but it is within range of what a lot of folks run it at. I'm using a Hammond choke that measures about 82 ohms, so some series resistance there would help bring it down for anyone concerned (or one could use the 6H Triad choke which is 150 ohms). I'd say the B+ in "300B mode" is right where it should be.

I've run the amp for an hour or so with the 300Bs and the transformer is only slightly warm. I'll let it go for a few more hours to let is heat soak. It does have a slight mechanical buzz, which is a little sad, but it's not too bad.

I had to put a fan on it because the tiny temporary heatsink on the heater regulator is not enough. It keeps tripping the thermal protection. The heater windings are where they ought to be. A tad on the high side, but not too bad.

[Wavebourn]

Originally posted by G



Did you drop it or something?

No, I shipped it by FedEx...

Design of bells is toyish. Period.

Buying Edcor transformers you need to consider ordering of mounting hardware somewhere else.

[rknize]

I've never seen mesh-plate tubes in person before. They are strange and cool at the same time. Is the blue glow on the glass typical? I mean, it makes sense given there are holes in the plate, but it has a bizarre pattern.

[rknize]

Originally posted by Wavebourn
Design of bells is toyish. Period.

Buying Edcor transformers you need to consider ordering of mounting hardware somewhere else.

i would agree about the mounting flange. The bells are fairly thin sheet metal and the tabs are stamped right into it. You can bend them with your fingers. I would not expect them to survive shipment anywhere mounted by them. I meant to ask them if they offered bells for flat-mounting them.