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City: lawrenceville nj
philco 40-844 portable
http://www.nostalgiaair.org/pagesbymodel...013558.pdf
started recapping
surprised that the rubber wire is still good pliable not crumbling
[Image: http://i1303.photobucket.com/albums/ag14...ewe3hw.jpg]
found one cap off the switch#42 that took a dump
[Image: http://i1303.photobucket.com/albums/ag14...n8dtog.jpg]
replaced the candohm was dead
[Image: http://i1303.photobucket.com/albums/ag14...hetpji.jpg]
[Image: http://i1303.photobucket.com/albums/ag14...bxybqj.jpg]
replace all electolytics
well turned on first time
lot of static no stations (no antenna connected and in metal building)
but still should get some thing. left on 15 min then static went away no sound at all
turn off. checked all seams ok. turned on. low volume static then went away, wiggle tubes little static here and their
then 117z6 tube stopped working
not looking good
think terry was touching chassis
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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That's a nasty lookin' cap there sam!
Posts: 7,283
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City: Roslyn Pa
You gotta put the 1lh4 back in JEEZZZZZZ!
Here's a better schematic:
http://www.nostalgiaair.org/pagesbymodel...013559.pdf
The one you posted has a shortwave band on it.
Check the off/on sw and clean the AC/Battery sw. After clng plug the cord into the chassis a few times to actuate the switch. Do you have 117vac across pin 2&7 on the 117Z6? Is the heater lit?? Measure the resistance across pins 2&7 on the tube with the tube unplugged. Should have a low resistance if open tube is bad. If tube is bad you can replace it with a 1N4007. No heat and no warm up time but does raise the filament voltage from 9v to about 10.5( measure from B- to pin 1 of the 1LA5).
I've been a glutton for punishment lately, have been working on a RCA 3BX571 Stratowave( read 1953 5 band rca am/sw portable ac/dc/battery). Audio and If are working but the mixer isn't (read uses 1L6 tube @$40 a pop). Going to try rigging up a 1R5 to see if that 1L6 is the problem.
Terry
(This post was last modified: 06-11-2016, 04:30 PM by
Radioroslyn.)
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Hey Sam is that a 2 or 3 gang tuning condensor? looks like the photo got cutoff. Some of these portables are very sensitive.
Paul
Tubetalk1
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Hi Paul,
It's got a two section tuning cap. No RF amp but two triode tubes for the mixer and oscillator, read quieter front end (1LE3's) Sports two IF amps, more gain than just one. (1LN5's). It's a pretty good sounding set for a portable.
Terry
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Many of the vintage portable surprise me.
Good luck doping it out.
pul
Tubetalk1
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terryy
will more checking monday
what do you think took out that cap was a .05
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
Posts: 7,283
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City: Roslyn Pa
The cap you took the pic of?? Looks like it was the main bypass and really tired of seeing 120vac across it. Fairly common fate. See Mike it failed open!
Terry
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City: lawrenceville nj
terry
measure from B- to pin 1 of the 1LA5
their is no 1LA5
cleaned switches . checked over
found the 1000v cap on wrong terminal
move to right spot
replaced 117z6 . turned on vol all the way up nothing
touched center vol tap loud buzz . connected ground of meter to b- where all electrolytic grounds are
touched pins but could only get .042 v and a lighting bolt shows on my meter will change battery ?
on the 1LN5 tube (not the floating plate one) when I touch white wires loud buzz and loud hum
if I wiggle the far right 1LE3 tube static comes and goes loud and low
and I replaced all tubes with known good working ones
side note spare 40-843 chassis I have connected power to it and would you know
fire right up and picked up stations with old caps
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
Posts: 7,283
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Joined: Dec 2009
City: Roslyn Pa
Sorry OM meant 1LB4 the audio output tube. Pin 1 is the start of the filament string and should be at about +9vdc from B-.See post #8 for the filament wiring.http://philcoradio.com/phorum/showthread.php?tid=14647
>touched pins but could only get .042 v and a lighting bolt shows on my meter.
Not sure what pins you were touching so can't tell you what you should see. Only worry if the lighting bolt come out of your meter!
Would clean the toob sockets with a small tool, I used a small dremel cutting bit manipulating it by hand. This may fix the intermittent at the 1LE3.
With the set plugged in to an isolation transformer use a signal generator to inject a 455kc modulated signal the pin 2 of the 1LE3 at the rear of the chassis (mixer toob). If all is well should hear the signal in the spkr. At this point you can peak up the trimmers on the three IF transformers. If you can't hear the generators signal try injecting the signal on pin 2 of the 1LD5 closest to the tuning cap (1st IF amp). If you still can't hear it go to pin 2 of the next 1LD5 (2nd IF amp).
Terry
(This post was last modified: 06-14-2016, 12:31 PM by
Radioroslyn.)