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

Shadograph question
#3

Yes. A bit, not much movement of the shadow has been achieved moving the lamp. Also with the current lamp position the lighted segment is very symmetrical and is dead in the middle of the screen, while if moved it goes left-right.
At this point I am more interested in the sensitivity and the current supplied by the input tubes.
I probably need to look at the AVC voltage from the detector tube 37. Don't know the exact range.


The AVC voltage reaches -4.5V, right where the 100K resistor from the detector, the #50, meets the volume pot and the other resistors.

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
Shadograph question - by morzh - 11-27-2016, 02:42 PM
RE: Shadograph question - by Ron Ramirez - 11-27-2016, 04:11 PM
RE: Shadograph question - by morzh - 11-27-2016, 04:29 PM
RE: Shadograph question - by morzh - 11-27-2016, 05:12 PM
RE: Shadograph question - by Radioroslyn - 12-01-2016, 07:38 PM
RE: Shadograph question - by Mondial - 12-01-2016, 08:12 PM
RE: Shadograph question - by morzh - 12-01-2016, 11:04 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
Tim - Photos of 8 octal tube sockets. (Top and bottom) Send me a PM if you're interested.RodB — 04:11 PM
VTVM meter moves when my hand is next to it & not on
Haha! I hope so. It seemed rather lost and forgotten languishing in the frozen Northeast of England.EdHolland — 02:36 PM
VTVM meter moves when my hand is next to it & not on
Ed - it's in the Cayman's enjoying the good life.RodB — 02:14 PM
VTVM meter moves when my hand is next to it & not on
Static electricity - but the other chaps beat me to it again. I've seen this before with analogue meters. I've also ...EdHolland — 01:56 PM
Need to purchase some accessories for restoration of my Old Philco Radio
Hi Paulo, Welcome to the Philco Phorum. I can see why you want to find good reproduction parts. That is a bea...MrFixr55 — 11:10 PM
HiFi (Chifi) tube amp build - but my own design.
Tim, I have some bakelite sockets in my work shop that I can dig up. I believe quite a few are NOS. I will take photo...RodB — 10:03 PM
Philco 610B oscillator wiring
> The cathode as noted is wired directly to the ground side of the heater filament for that tube, not to the #17 and ...Radioroslyn — 08:12 PM
HiFi (Chifi) tube amp build - but my own design.
Tim; I noticed your post a little late, but I would take one of the junk sockets and try to break a chunk out of it wi...Arran — 08:07 PM
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM

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

>