I've been tagging along someone else's thread and it's time to start mine. Well along in the build and I'm stumped with the primary wires on the Hammond 270fx.There Black/Grey & White. Also need assistance with the 125ese. Testing phase is fast approaching if I can get this hooked up right.
https://www.google.com/search?q=ham...ndoutputtransformer125ese.aspx&source=iu&pf=m
https://www.google.com/search?q=ham...ndoutputtransformer125ese.aspx&source=iu&pf=m
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The older Hammond power transformers only had 2 wires for the primary. They were designed a long time ago when the US line voltage was about 115 volts. Our line voltage is quite a bit higher today, so these old Hammonds were famous for putting out too much voltage.
If your line voltage is in the 120+ volt range (mine is 122 to 124 volts) then use the white and black wires. Tape up or otherwise insulate the grey wire, do not connect it to anything.
The 125 series uses a single primary winding and a multi tapped secondary to give a wide range of impedance values.
For a 45 tube and 8 ohm speakers, use the yellow and black wires for the speaker connections, tape up the others. For a 45 with 4 ohm speakers, use the green and black wires. The black wire is the "cold" side and should be grounded.
After the amp is running properly you can try all the different taps (keep the black wire connected, just try the different colors to see which really works best with your tubes and speakers.
In theory is makes no difference which primary wires (brown or blue) goes to the plate or B+. In practice a small difference may be heard due to stray capacitance. After the amp is making good sound you may try swapping the wires. Keep both channels wired the same at all times to avoid having an out of phase channel resulting in loss of bass.
If your line voltage is in the 120+ volt range (mine is 122 to 124 volts) then use the white and black wires. Tape up or otherwise insulate the grey wire, do not connect it to anything.
The 125 series uses a single primary winding and a multi tapped secondary to give a wide range of impedance values.
For a 45 tube and 8 ohm speakers, use the yellow and black wires for the speaker connections, tape up the others. For a 45 with 4 ohm speakers, use the green and black wires. The black wire is the "cold" side and should be grounded.
After the amp is running properly you can try all the different taps (keep the black wire connected, just try the different colors to see which really works best with your tubes and speakers.
In theory is makes no difference which primary wires (brown or blue) goes to the plate or B+. In practice a small difference may be heard due to stray capacitance. After the amp is making good sound you may try swapping the wires. Keep both channels wired the same at all times to avoid having an out of phase channel resulting in loss of bass.
Is this what you have with the 270fx? https://www.google.co.uk/search?q=H...sAQILg&biw=1366&bih=638#imgrc=VfbMVhKSJnGsQM:
Ah, too slow!
Ah, too slow!
Thank you very much to the both of you. I'm going to make George proud. My top plate's ordered and if I can stop making kindling out of the wood I'm going to use as a base we may just have something here.
I see AES sells these tube savers. The sockets I have grip. Much more that my other 4 pins do.
I see AES sells these tube savers. The sockets I have grip. Much more that my other 4 pins do.
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Not the sharpest knife in the drawer. Wheres my connection to test filament supply.?
An externally hosted image should be here but it was not working when we last tested it.
That wasn't the reason voltage is low. With a rectifier tube in voltage is 200 both sides. Guess I'll run with it. Here's my second attempt at a base. My top plate has been shipped.
An externally hosted image should be here but it was not working when we last tested it.
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