Finally remembered. I'm 95% certain the schematic below is identical to the 4359A but it's been months since last playing with this hardware.
An externally hosted image should be here but it was not working when we last tested it.
OK, I give up. How do I get that thumbnail schematic to enlarge, it doesn't work for me. Got a direct link?
Nor me...
I dont no this output (sekundar) kabel from transformersHi,
i search schematics for rowe ami mm4 with 7868 pentode
I have from this amp outputs transformers.
Thank you.
this color ist:
Black
brown-white
white
yellow
green
green-white
green-yellow
Hallo to All of you, I'm new to this forum.
Please, can any one help with ROWE AMi R-4359A schematic diagram.
I would like to repair this amp.
Thanks a lot
My memory of this amp is dimmer than six years ago but I believe this was very close to mine. Due diligence circuit sleuthing recommended.
Attachments
I also have one of these amps (R-2620).
I was looking at the tertiary winding on the OPT, and saw that some had wondered about using it for CFB. Has this been tried? It has a center tap, and supposedly is for 70v line out. The center tap is linked to the speaker ground tap on the secondary.
I was looking at the tertiary winding on the OPT, and saw that some had wondered about using it for CFB. Has this been tried? It has a center tap, and supposedly is for 70v line out. The center tap is linked to the speaker ground tap on the secondary.
...the tertiary winding on the OPT....wondered about using it for CFB... supposedly is for 70v line out. ....
If it is 70VCT--
The peak voltage across half the winding is 49V. This at the cathode increases the required grid swing.
The stock grid swing is about 18V peak. (The 14V test-point is dragged down by meter loading.)
So we need 18V+49V= 67V peak grid swing. On two grids. From a cathodyne biased at only 56V per side. It can't reach full output.
And what you might gain by a smaller NFB loop, you lose in less NFB in the global loop. As-is, it has very little global NFB. With CFB it has "none" in the global loop. (Unless you change global NFB for much lower gain, forcing a larger input signal and more work for the stage before this.)
Some amps beg for change. IMHO this one doesn't.
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