Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Bush Radio DAC 90A
#2

Arran


Depends on your load. It is a Greinacher scheme, so maybe it does not matter as the voltages are simply added to each other and if one is lower than the other, so what, it simply is losing a few volts due to higher impedance of the tube.
This said, unless you want to keep the radio AC/DC and use that tube's filament for that reason, you could use a cap to trim the votage to the load of one less tube.
Or you could use the tube's filament, but then not use the rest of it, and use 2x1N4007.

Also, look up my Telefunken thread from a year ago: there is a thing about the common going to one of the lines, without which there will be hum.
I also experimented with the input and output caps; their ratio will determin the output voltage.

https://philcoradio.com/phorum/showthrea...telefunken

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Bush Radio DAC 90A - by Arran - 04-21-2024, 07:11 PM
RE: Bush Radio DAC 90A - by morzh - 04-21-2024, 07:47 PM
RE: Bush Radio DAC 90A - by Arran - 04-21-2024, 08:38 PM
RE: Bush Radio DAC 90A - by morzh - 04-21-2024, 09:39 PM
RE: Bush Radio DAC 90A - by Arran - 04-24-2024, 11:27 PM
RE: Bush Radio DAC 90A - by Arran - 04-28-2024, 03:13 PM
RE: Bush Radio DAC 90A - by Arran - 04-30-2024, 01:48 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
The list of my radio & TV collection!
For fans of antique radio... My new video... How to test radio tubes on a Hickok 530B tube tester? Test radio tubes o...RadioSvit — 01:25 PM
philcorepairbench.com - shadow-meter
Thank you Billpoulsbobill — 11:53 AM
philcorepairbench.com - shadow-meter
Hi, Try here Philco Service Hints & Tips, Number 1 It's from the web archive (Way Back Machine).Keith — 10:17 AM
PT-6 finished!!
Hi Arran,  Yes, you are correct, the "nominal" voltage for these Loctal tubes was the same 6.3 or 12.6 V as...MrFixr55 — 07:48 AM
PT-6 finished!!
Actually the Loctal tube series, with number beginning with "14" are 12.6 volt tubes, at 150 ma, I'm not sure ...Arran — 02:14 AM
philco predicta
The model is the holiday without UHF It has no sound and I don't have an oscilloscope or signal generator.cgl18 — 08:51 PM
Philco model 38 code 121 not receiving signal.
I will definitely check my lead length and wire dressing. Thanks for the ideas.Stormlord5500 — 08:06 PM
Philco model 38 code 121 not receiving signal.
Do make sure that you twist the 3 wires from the chassis to the transformer, and dress away from tubes, especially audio...MrFixr55 — 07:38 PM
Philco model 38 code 121 not receiving signal.
The cone unfortunately got damaged when I removed it. The glue that held the cone to the basket was sloppily applied and...Stormlord5500 — 07:12 PM
Philco model 38 code 121 not receiving signal.
So what was wrong with the original speaker? Was the cone damaged? Unless it's totally hopeless I would put it aside as ...Arran — 05:31 PM

[-]
Who's Online
There are currently no members online.

>