Hello from justinis

[justinis]

Thanks! I have simulated parts of the amplifier using LTSpice and Duncan PSU designer, but not the whole thing. That would be intense!

[FerdinandII]

Yup, PSpice is the way to go, if you want to go there.....

I was thinking more of simulating the entire amplifier.

[brombo]

For those old to remember SPICE is a digital implementation of an analog computer (I once used a Heath-Kit analog computer in college). The most complicated simulation I used SPICE for was a linear diesel engine directly connected to an alternator for a hybrid vehicle study.

[FerdinandII]

Where's the "Like" button.....?
Oh, here it is:

For those old to remember SPICE is a digital implementation of an analog computer (I once used a Heath-Kit analog computer in college). The most complicated simulation I used SPICE for was a linear diesel engine directly connected to an alternator for a hybrid vehicle study.

In, before Roscoe -

[brombo]

For those that are interested attached are pictures of the Heathkit analog computer and a schematic of a linear diesel alternator -

Attachments

[FerdinandII]

You have exceeded expectations.......!
Cool stuff.

[dberning]

Welcome, Justin. The choke input to the filter is an excellent way to reduce the B+ voltage. The requirement for proper operation is that the choke must remain in continuous-current mode of operation. This means that the current never goes to zero. So sufficient loading of the power supply is required for the value of the choke used. If this requirement is met, you get the RMS value of the dc voltage from the rectifier rather than the peak voltage. So forgetting parasitic losses, a 300-0-300 volt transformer will give you about 440 V dc if loaded with a capacitor, but 300 V dc with the choke input to the filter. The regulation is generally better with the choke loading because the transformer does not have to deliver high peak capacitor-charging currents, and the rectifier resistance becomes less of an issue as well. Do note that if no current is drawn from your B+ supply while other tubes are warming up, the voltage will rise to the peak unloaded transformer condition, which in the above case might be over 500 volts.

David

[J-ROB]

Justin,

If you want a good old school lesson on tube power supplies (and many other germane topics) try to find a early-70s or earlier copy of "The Radio Amateur's Handbook" by ARRL.

Shouldn't be hard...there are a zillion copies of this perennial annual in print.

[justinis]

Thanks J-ROB and dberning!