PP Amp kits qua Dyna ST-70?

[Paul Joppa]

FWIW, I placed a couple of ads for ST-70 road kill (AA Trader & US Audio Mart), and now I will wait.

At one time I was into handmade antique carpets (on the cheap end of the scale!!) - we call them "noble wrecks". Sometimes you just have to make a cushion out of the good parts of a worn-out rug.

[Paully]

I know this is the Bottlehead site, but since most of us here have a Bottlehead amp in addition to our Dynaco, for those who have one, so post your progress.  I have built one from the chassis up and rebuilt another and that was my entry into tube audio before Bottlehead.  So I will be very interested what direction you take as you go.

[Downhome Upstate]

FWIW, I placed a couple of ads for ST-70 road kill (AA Trader & US Audio Mart), and now I will wait.

At one time I was into handmade antique carpets (on the cheap end of the scale!!) - we call them "noble wrecks". Sometimes you just have to make a cushion out of the good parts of a worn-out rug.

I like that, Paul, altho' I had to stop for a minute and think it through. A cushion it will be, then.

[Downhome Upstate]

I know this is the Bottlehead site, but since most of us here have a Bottlehead amp in addition to our Dynaco, for those who have one, so post your progress.  I have built one from the chassis up and rebuilt another and that was my entry into tube audio before Bottlehead.  So I will be very interested what direction you take as you go.

Yup. I'm kinda doing this backwards. But better Nate than lever.

[Downhome Upstate]

Just paid $300 + shipping for a functional ST-70 sans tubes and cage.  I missed out on a listing on DIY Audio for a Tektronix 2215. Maybe its time to look for another 'scope and some probes.

[Paully]

Sweet! The upgrade process begins. Check your bank account. As always, the can cap is the first thing to deal with. Then the driver board, then the old tube sockets, maybe a new power transformer...  Good luck!

[Paul Birkeland]

Sweet! The upgrade process begins. Check your bank account. As always, the can cap is the first thing to deal with. Then the driver board, then the old tube sockets, maybe a new power transformer...  Good luck!

Selenium rectifier?

[Downhome Upstate]

Sweet! The upgrade process begins. Check your bank account. As always, the can cap is the first thing to deal with. Then the driver board, then the old tube sockets, maybe a new power transformer...  Good luck!

Selenium rectifier?

How 'bout that stock GZ34 rectifier?

[2wo]

"Selenium rectifier?

Its between the power transformer and the PCB, for the bias. Replace it with a diode first thing...John

[Downhome Upstate]

Sweet! The upgrade process begins. Check your bank account. As always, the can cap is the first thing to deal with. Then the driver board, then the old tube sockets, maybe a new power transformer...  Good luck!

After I have a look under the hood, up close and personal-like, I was thinking about ditching the can cap. The Triode Electronics power supply capacitor board looks good. It mounts underneath one of the OT and has 500 uf of filtering. $77.

[Downhome Upstate]

"Selenium rectifier?

Its between the power transformer and the PCB, for the bias. Replace it with a diode first thing...John

Thanks, John. Had my first look at the schematic today (the 7199 pentode/triode was a head scratcher).

[Grainger49]

The Curcio cap board replaces both the can cap and bias supply, Selenium rectifier.  Paully put that in his first ST-70.

[Paully]

Doesn't the Triod Electonics do the same?  We put that one in the current Dynaco.

[Downhome Upstate]

Hey, guys. Where does the selenium rectifier appear in the schematic in the product manual?

[Downhome Upstate]

The Curcio cap board replaces both the can cap and bias supply, Selenium rectifier.  Paully put that in his first ST-70.

I hadn't seen Curio's web pages before. As Werner Klemperer said, "very interesting." But it looks like their upgrades are for triode operation only. I'd like to get as much power out of the ST-70 as possible, and it looks like the sources for ultralinear upgrade boards and parts are at Triode Electronics and tubes4hifi.