Here’s what the PT is doing unhooked.
Checking continuity, between yellow wires, .6 ohm, between red, 331 ohm, green to green .3, so there’s no major shorts in there, but:
measuring ac voltage with a true rms dmm
Across green wires 6.79 vac, and across yellow 5.3. Is that right? If those are half what they are supposed to be, could I run one…[Read more]
I checked impedance of leads to OT, and there are no shorts. The ohm reading were what are to be expected. I powered up with the primary connected and the red yellow grounded. Unconnected, across the leads(not to ground) I got 6.5vac for green wires; 5.15 vac across yellow, and 660 vac across red.
I always have the output to a speaker or an…[Read more]
I recently moved to NE Arkansas, and a frequent conversation includes statements like “I lost my (wife, job, house, limb) from when I used to smoke methamphetamine.” Never meth.
well, I don’t even have that excuse. So of course I had a found to the ground lug off one of the green wires, so now am getting 3.2 off of each green wire, and so each t…[Read more]
Update. I have dc voltages on the filter caps that look ok, at 376,338,and 241 big to small. DC
On a 6V6 there’s 373vdc at pin 3, and 340vdc on pin 4 with 122 vac from my variac so that’s all high, but there’s hum to the speaker now, that doesn’t change with volume or tone, and scratching sounds from the speaker when the tube pins are probed.…[Read more]
I promise I’m not stupid, but I am left handed. I looked at the diagram from the perspective of outside, so all my tube wiring was backwards. Yikes. I’ve used the lightbulb and a variac, so hopefully we’ll be ok. I’ll rewire it, and check grounds and cross fingers and toes.
Thank you all for the assistance. I make pretty good acoustic guitars…[Read more]
Howdy. I’m not a moderator or expert, but I don’t see why you’d need the switch, assuming you use one tube/ speaker combo. Page 188 of the old book has the output info for the wires from the OT.
You may want to use the Contact form to get the mod to see your post. That’s what I did, and they got right back to me.
I’ll go back through it, check the values and grounds, and let you know. I ordered another tube, so I’ll have that option/ diagnostic tool as well. I’m learning a lot, as I guess all new builders do. I just don’t know what I don’t know. I’ve got questions on the impedance switch, but will try to get it running first.
Thanks for the hel…[Read more]
I think we’re mostly on the same page. I have the center tap done, and my low voltage ac is ok. The problem is that there’s 330ac on the yellow wires going into rectifier tube pins 2&8, but no power coming out of pin 8 to the first filter cap. I have a white cloth covered wire going from pin 8 to the first cap and on the same post, the 5w/…[Read more]
I bought the 2 stroke kit here years ago, and am now just getting around to building. I know some parts are different from the book,(which I have of course), but the supplied addendum is incomplete or wrong. In the discussion of the new PT, he seems to mean the OT, and none of the descriptions of the PT match what I have. Mines closest to…[Read more]
I’m building my first amp, and it’s going fairly well, but this section of the book has me baffled. I don’t even know what question to start with. Here goes: the kit seems not to have a brass plate, and so how will I accomplish the rest of pp 6 instructions?
Also, and scarily ” now solder the ground connection from output tube….” I see in…[Read more]