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

Dragging out an old nemisis-Philco 66 cathedral-SUCCESS
#5

Good catch, morzh. My old man eyes failed to notice the tiny little m in front of the V. I ran major resistances, and R44=254.5, R27+R29=140K, both coils gave good numbers for primaries and secondaries, choke is 2400, field coil=1200, output transformer is good, and both IFs have good windings. Used a dim bulb and variac to bring the set up with no tubes in, and the bulb stayed dark. While under load, the bulb has a dim glow going on. All heaters run about 2.3v.
voltages:

80:filaments=4v, plates=300 different and lower.
42: plate=205, screen=209, grid=-6.4, cathode=0
6A7:plate=213, screen=76, anode grid=136, control grid=1.9 (positive voltage) and grid cap= +1.9
78: plate=212, screen=75, suppressor and cathode (pins 4 & 5 are connected)=1.6, grid=1.6 grid cap= -82mv
75: triode plate=148, diode plate=-96mv, cathode=.1, grid=0 grid cap= -.5

Still gets buzzing where it did before. I need to get the heater voltage higher and the 6A7 grid in the negative, right? I still wonder about the grounding for several components, so I will look there (especially the ones that have their grounded sides connected together on the daughterboard (are all 66s done that way?). I also have the service note components i this set (the 20K resistor off the bandswitch, the 70 ohm resistor in the oscillator coil.

That's it for tonight. I'll think about it tomorrow as Scarlet says.


Messages In This Thread
RE: Dragging out an old nemisis-Philco 66 cathedral - by ccomer1955 - 08-11-2014, 01:52 AM



Users browsing this thread: 3 Guest(s)
[-]
Recent Posts
Another amp build - here I go again!
Well, never enough yet how much is too much? I ordered some spare parts from a couple vendors in China and now have ship...TV MAN — 10:49 AM
A Marconi model 86
This Marconi was a bit of a challenge. It was totally missing one electrolytic  capacitor, and the photos show a couple ...Dan Walker — 10:48 AM
Philco 42-345 Restoration/Repair
With regard to the speaker, unless the cone is so brittle that it crumbles as soon as you touch it I would try to repair...Arran — 04:07 AM
Philco 42-345 Restoration/Repair
That silver can capacitor is an aluminum electrolytic. You should replace it with an aluminum electrolytic with the valu...RodB — 11:46 PM
Philco 42-345 Restoration/Repair
Thank you Rodb and Gary for helping with clarification on these capacitors. Other than the Tiny 630volt one I'm not sure...osanders0311 — 10:17 PM
1949 Motorola 5A9M
Hello All; I found the CMB41L down in the basement, it is definitely a 1950-51 model, the capacitors have date codes ...Arran — 07:48 PM
Philco 42-345 Restoration/Repair
Hi, all the caps I order, other than the electrolytics, are of the 630V rating. No worries on it being too high, and no ...gary rabbitt — 05:46 PM
Philco 42-345 Restoration/Repair
Hi, there's a lot to consider when designing these circuits so you shouldn't have a lot of concern when replacing caps. ...RodB — 02:03 PM
Philco 42-345 Restoration/Repair
I have ordered and received new caps for this radio and hope I've ordered the correct ones. I tried matching them to the...osanders0311 — 11:35 AM
Philco newbie with P-1891-WA console questions
Hello Jeff , Far as the Electrolytic capacitors go here is a list of parts. that will work . I like using Nichicon and...radiorich — 09:50 PM

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

>