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

crazy issue 41-604 works fine with dim bulb
#1

Hello Guys,
One of the guys I know in our hobby is having problems with his newly restored Philco 41-604 when he brings it up on full line voltage the set starts acting up but if he runs it on Dim bulb it works just fine .https://philcoradio.com/library/download...20Book.pdf
Anyway Ideas .


Sincerely Richard
#2

Define acting up? It looks like an AC/DC set judging by the diagram. I'm really just shooting in the dark here without having an idea of what is going on, but if all the capacitors have been replaced, correct values, correct voltage ratings, in the correct places, then it could be something like a gassy tube, or secondary emission from a grid. It also could be that a carbon comp resistor is failing, more voltage, more heat, and the connection inside is breaking down.
Regards
Arran
#3

Hello Arran,
Yes He replaced all the capacitors !

Sincerely Richard
#4

Rich

I will repeat Arrans request:

- Define "acting up".

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.
#5

Hello Arran and Morzh,

Here is what he wrote me " By act up, I mean it squeals and distorts between strong stations. Also, I have a strong station that shows up at multiple different frequencies."

he just ordered an NOS 7C6 tube because the original tube seems to have an intermittent issue.

Sincerely Richard
#6

Quote:By act up, I mean it squeals and distorts between strong stations. Also, I have a strong station that shows up at multiple different frequencies."
I would look to miss connections, wrong cap/resistor values, shorts between terminals, solder blobs, wire snips, solder flowed between tube wafer contacts, poor riveted joints to chassis, even if the "best ohmmeter" says the joint is O.K. There could be corrosion issues with the coils, if resistance readings are higher, then there is a problem. The band switch must be cleaned with 91% alcohol and gently blown dry, use of "miracle" contact cleaners can result in leakage. Poor connections in the band switch could also be a possibility...

Re-wiring and not following the route of the original wires, especially in the RF/OSC and around the volume control, missing tube shield(s).

Overall, if the "shotgun method" was used to refurbish, that, in of itself, is responsible for the outcome.

It generally takes stage by stage analysis after eliminating a power supply issue if any to recover from cited issues.

Poking the chassis components with a tongue depressor, with set in operation, will often reveal oscillations occurring from juxtaposition.

GL

Chas

Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
#7

>>Poking the chassis components with a tongue depressor,

Chas,

Tongue depressors only depress tongues...and their owners. Icon_smile
#8

hello Morzh,
Yes I had to to poke and press items on modern printed circuit boards to get sets to act up also the use of cold spray and heat .

Sincerely Richard
#9

Quote:Tongue depressors only depress tongues...and their owners.
Many, many common "tools" can be "MacGyver'd" into service to serve another purpose. I also use the T.D. whittled a bit to apply wood filler in difficult places. One end sharpened to a point it becomes a marker in the flower bed...

To suggest the use of a pencil to poke a circuit has some risk, I could suggest a Delrin or Teflon rod but not many have a such laying about. A wooden dowel, fine, even the "Popsicle" stick, after consuming the quiescently frozen confection and drying the said stick.

Chas

Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
#10

I prefer a bamboo chopstick for poking around looking for issues. Usually get them with an order to go at our local Chinese restaurant. Kills two birds with one stone! Take care and BE HEALTHY! Gary

"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
#11

>>Kills two birds with one stone!


Exactly. First you use them to eat your Peking Duck, a bird #1.

   

Then you tap on the chassis of that one.

   

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.




Users browsing this thread: 3 Guest(s)
[-]
Recent Posts
The list of my radio & TV collection!
Hello Peter, Thank you for posting that !! Sincerely Richardradiorich — 09:40 AM
Eico 232 VTVM Schematic
It's a microwave antenna. ?;-p?. I substituted 1N4002s off the 6.3 vac winding for the 1.5 volt battery. Uniprobe is the...RodB — 05:50 PM
Eico 232 VTVM Schematic
Try BAMA for a schematic. Looks like a replacement power source for the D battery has been installed. The tube may be...Chas — 04:51 PM
Eico 232 VTVM Schematic
Is that a battery holder?morzh — 04:43 PM
Eico 232 VTVM Schematic
A friend gave me this Eico 232 VTVM and I'm having trouble locating the schematic for it. This one seems to be a later v...RodB — 04:17 PM
Var resistor id
Considering what it is in series with, I doubt there should be any power requirements. Of course, we should know wher...morzh — 03:23 PM
Var resistor id
Trim pot, about 1/2 watt part of focus divider. As stated 2k ohms. This appears to be a rusty chassis, resolder all ...Chas — 03:19 PM
Var resistor id
Its a Sylvania 400 oscilloscope. here is a clip of r-100. Would be nice to know the current required. Not listed in part...Martinj — 02:10 PM
The list of my radio & TV collection!
Thanks Richard. I hope you enjoy it. Here I have created an English section on the history of radio with videos in Engl...RadioSvit — 10:23 AM
The list of my radio & TV collection!
Hello RadioSvit, first all happy new year ! I will watch your new videos this week. Sincerely Richardradiorich — 09:19 AM

[-]
Who's Online
There are currently 9360 online users. [Complete List]
» 1 Member(s) | 9359 Guest(s)
Avatar

>