THE PHILCO RESTORER

Transcription

THE PHILCO RESTORER
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THE PHILCO
RESTORER
ca
1928
This Site is dedicated to the restoration of PHILCO Radio chassis and
cabinets from 1929 thru 1942. This site is for the newcomer (newbie) and
novice and not really the expert.
Things covered in this web site are:
Supplies and tools for the restoration of chassis and cabinets for the
newbie. Schematic's and Symbols: How to use them. PHILCO bakelite
capacitors; don't be afraid of them. PHILCO resistors
before R.M.A.. Soldering, PHILCO wiring and how to repair it.
PHILCO paper capacitors and PHILCO Mica capacitors and what to do
with them. Tubes and how to read them. PHILCO vintage test equipment.
Resources, where to buy the stuff. PHILCO model and part numbers
explained. How to refinish cabinets my way. PHILCO photo finishes in
1937. PHILCO R.M.S. repair service.
Never to busy to help some one out
CLICK BELOW TO SEE WHAT I HAVE TO SAY
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MODEL, PART NUMBERS EXPLAINED
PAPER CAPACITORS
PHILCO RESISTORS
SOLDERING
PHILCO WIRING
MICA & SILVER MICA CAPACITORS
ELECTROLYTIC CAPCITORS
REBUILDING PHILCO BAKELITE CAPACITORS
PHILCO SERVICE BULLETIN NO. 289 - 1ST PAGE
PHILCO SERVICE BULLETIN NO. 289 - 2ND PAGE
OTHER PHILCO ITEMS OTHER THAN RADIOS
SCHEMATICS & SYMBOLS, How to use them.
HOW TO GET PHILCO INFORMATION
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MODEL , PARTS NUMBERS EXPLAINED
MODEL, PART NUMBERS EXPLAINED
Model, Parts Numbers Explained
PHILCO marketed their first radio in 1928 with the model number of 511
and used 2 and 3 digit numbers up until 1937, when they started using
suffixes for cabinet styles. So if you had a 95 chassis, that could be in any
console cabinet with 65 being a 6 tube chassis, 76 being a 7 tube, 86 or 87
being a 8 tube and a 95 being a 9 tube chassis. Like a 95 highboy or a 87
highboy or even a 76 deluxe highboy. In 1937 they started using 37-9X or
37-61B for example. The first 2 digits is the year, 37 for 1937 and 41 for
1941 for example.
PHILCO's part numbering system also has some numbers that appear to
be year model numbers, for example the 39-6347 is printed matter and
36-5521 is speakers. So 27- is for bakelite parts, 28- metal parts, 30fixed condensers, 31- variable condensers, 32- transformers, 33- resisters,
34- tubes and bulbs, 35- phongraph parts, 36- speakers, 37- chassis, 38sub-base, 39- printed matter, 40- accessorys, 41- motors, 42- switches, 43major sub-body's, 44- speaker cloth, and 45- hardware.
Mistakes useally happen when looking in a cabinet and you see 39-5587,
that's the part number for the label, not for the radio model number.
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04/05/2012 23.19
paper capacitors
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PAPER CAPACITORS
First of all capacitors is a term that was not always used. The word
condensers was used for a very long time and some place along the way it
was changed to capacitors. Most people call them "caps", so when you
read that a radio has been "recaped", that means that the capacitors have
been replaced.
The performance of the radio depends on the conditon of these "caps".
Most often they will be badly deteriorated and they should ALL be
replaced and NOT JUST the easy one's to get at. They are cylinders filled
with wax on the ends with a wire lead coming out of both ends.
Capacitors are found in all areas of the radio circuit for general
coupling, decoupling and filtering. They are NON-POLARITY sensitive
and are usually clearly labeled with the value and voltage rating. They
often have a black band around one end. This end was connected to the
less sensitive side of the circuit and for non-electrolytic ones it does NOT
make any difference which end you connect.
Damage to the caps is usually indicated by melting, bubbling or darkening
of the outer wax covering and loss of wax on one end. Sometimes they
look ok and test ok, but have electrical leakage and can act more like a
resistor.
It is hotly debated whether or not you should replace them all as purists
and collectors feel they should only be replaced if absolutely necessary.
Paper-wax capacitors are VERY prone to failure and it is just a matter of
time before they fail, so I believe they should ALL be replaced. Since the
work is under the chassis and not visible, it should have little impact on
the value. People who look at my radios have never asked me to take the
chassis out.
Before you expend a lot of effort trying to find the exact values, you come
as close as you can to the values. For example, a 0.05 cap you use a 0.047
cap, for a 0.02 cap use a 0.022 cap and so on. The voltage I use is 630
Volts on everything, that way you don't have to keep as many of them in
stock.
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paper capacitors
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04/05/2012 23.20
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PHILCO RESISTORS BEFORE RMA
PHILCO RESISTORS BEFORE RMA
The resistors used in the early PHILCO radios were color coded with
PHILCO's own system and were of the "dog bone" type. Other
manufactures like Atwater Kent also used their own unique system for
color coding. It was not until RMA (Radio Manufactures Association)
established the 3 color system that became the resistor color coding of
today.
Looking back, it did seem strange that PHILCO's engineers used some
of the different shades of color instead of a different color. Two
shades of gray were used, Battleship Gray and Silver Gray; 2 shades of
yellow, Yellow and Golden Yellow. Other colors had fancy names like
Jade Green, Auto Buff, Auto Broen and Belgian Blue.
The following is a list of these colors:
BLACK
BLUE
AUTO BROWN + YELLOW
AUTO BUFF
BATTLE SHIP GRAY
SILVER GRAY
SILVER GRAY + YELLOW
GREEN
JADE GREEN
ORANGE
WHITE
GOLDEN YELLOW
10.000 ohms
13.000 ohms
25.000 ohms
25.000 ohms
500.000 ohms
100.000 ohms
100.000 ohms
1 Megohms
70.000 ohms
50.000 ohms
250.000 ohms
5.000 ohms
(The colors used here are not exact)
All of these resistors appear to be 1 watt.
I think it is best to replace all resistors with 1 watt, except when a 2 watt is
called for in the schematic.
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04/05/2012 23.20
SOLDERING
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SOLDERING
This subject of Soldering and Philco Wiring is so important that I
decided to do it in two parts, the first half Soldering the second half
Philco Wiring.
Replacing the capacitors and resistors could lead to a disaster if not done
correctly. Be sure to work on recapping and replacing resistors a few
hours at a time. I know it’s fun but it’s very easy to make mistakes when
you are tired. Even worse you’ll find yourself compromising quality, as
you are anxious to get it working. Be patient and work carefully. If you
don’t have the time to do it right this time, you’ll never have the time to
do it again.
When you are done with the recapping and replacing of resistors, treat
the set as if there might be a short in it when you turn it on for the first
time. Be ready to quickly disconnect the power.
I have four (4) sets of locking forceps like doctors use. The paper
capacitors usually are much bigger than the new replacements and have
long leads. I clip the old capacitors up next to the body and clamp one
pair of forceps to the old wire and do the same with the other old wire
capacitor end; that way if I am interrupted or stop for the day, I have not
lost where the new capacitor goes. When I stop for the day I put the old
capacitor on the bench in front of the set, this way I know what value
goes where when I start up the next day. I had three (3) occasions when
I put the capacitor on the wrong terminal.
With the forceps, I put a ‘J’ hook in the old leads, a ‘J’ hook in the new
capacitor leads and crimp them together. Hold the iron to the terminal
or wire and heat it up, then start to apply the solder to the terminal or
wire, letting it melt the solder rather than the iron tip. Let the solder
flow liberally around the joint. Be sure to keep the wires steady as the
joint cools and always inspect the connection for “dry” areas. The
solder MUST bond well to both metals being joined and the joint shiny.
A word about after the soldering is done. Take your forceps and pull
the joint to make SURE the job is done right. I had two (2) occasions
where the radio did not work correctly and it took a long time to figure
out that the bad soldering joint was the problem.
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SOLDERING
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PHILCO made a lot of run changes to redress the wiring. I very seldom
completely remove the wires from the terminals. You can get yourself in
a lot of trouble doing that. Don’t move the wiring around a lot or
change the direction and location of it.
Keep a notebook and pen by the work area to make notes. It’s easier to
make notes for reference than to remember what you did when trying
to figure out what is wrong!
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04/05/2012 23.21
PHILCO WIRING
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PHILCO WIRING
Now a word about that wonderful PHILCO Wiring used in sets from
1939 to 1942 when production stopped for WWII. They tell me it was
rubber covered, but I really don’t know what it was. It was just awful
stuff! They tell me that the repair of PHILCO Wiring is not for the
NOVICE, but if you take your time, you can do it. All of the “rubber”
insulation breaks down over the years, dries out and flakes off. If you
turn that 40-150 chassis you just got upside down, you will see a lot of
bare wiring and partially bare wires that will brake apart when touched.
They even used it in their power transformers.
Some people just put sleeving over the wiring without taking the
transformer off. They slide the sleeving up the wiring inside the
transformer covers.
The problem with doing this is the wiring inside the transformer, under
the covers, is touching causing a short in the transformer. The only way
to do it right is to color code the wiring with paint dots and remove the
transformer. Remove the transformer covers and then put the sleeving
on, running the sleeving right up to the paper insulation.
The rest of the wiring can either be replaced or re-sleeved. Do one at a
time and try not to change the length or the route of the wiring. Use
heat shrink sleeving. If your going to replace the wiring use 20 Gauge
Cloth Covered Stranded Wire, do NOT use solid wiring. If you put a
nick in solid wire and you bend it, it will break. I have seen it break
inside of something and you don’t know it broke. A real hard thing to
find!!
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04/05/2012 23.21
MICA AND SILVER MICA CAPACITORS
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MICA AND SILVER MICA CAPACITORS
PHILCO Mica Capacitors are flat bakelite stamp sized square blocks or
small “pez” sized pills or even small cylinders. They are found in the
high frequency tuning and detecting stages of the circuit.
These caps are very durable and rarely need replacing unless they are
way off value, damaged or open. If they need replacing it’s usually
because they are open. By NOT replacing them, you can reduce the
amount of possible re-aligning required to get the set working well.
Mica Caps are usually measured in pF (Pico farads) and sometimes
nanofarads, and not uf (microfarads).
As long as we are talking about Mica Caps, they are also used in the
PHILCO Bakelite Block Capacitors. The block numbers they are used
in are :
8035-D
8035-ODU
8035-EU
8035-OEU
8035-DG
8035-ODG
8035-SG
8035-DU
8035-SU
8035-H
8035-G
8035-E
8035-F
8035-K
8035-L
8035-C
8035-B
8035-P
And are listed as 110 pF. Do NOT use 0.001 caps, use silver Mica
100 pF caps like the small one at the top of this page
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04/05/2012 23.21
Electrolytic capacitors
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ELECTROLYTIC CAPACITORS
They are commonly either large aluminum cylinders mounted to the top
of the chassis or large cardboard cylinders under the chassis with several
colored leads. Usually there are two (2) or more of them. They can be one
(1) part, two (2) parts or sometimes three (3) parts. Each part can have a
different voltage and value. These capacitors are used for power filtering.
They are VERY prone to failure and must ALWAYS be replaced. One of
the golden rules in antique restoration is NEVER, EVER plug a radio in
without checking the electrolytic capacitors, they may very well be shorted
and can burn up the power transformer.
Electrolytic capacitors are usually the reason for a loud hum or buzzing,
but are not always the problem. If you find one that is bulging or has
exploded, suspect that it is wired incorrectly. If they are mounted on top
of the chassis and are the can type, check to see if they are mounted in a
cardboard cylinder or if there is a fiber washer between the can and the
chassis. If there is a washer or cardboard cylinder, they are not grounded
to the chassis.
Take a look at the blue and black capacitor at the top of the page. Notice
the arrow on the side of it. The arrow is pointing to the NEGATIVE end
of the capacitor. If it has wires the NEGATIVE wire is black. Notice I
did not say ground!! It’s NEGATIVE. Electrolytic capacitors ARE
polarity sensitive! You must have them wired positive to positive and
negative to negative. Now they MAY have negative to chassis ground,
and they MAY not. If you don’t know which way they go, FIND out,
DON’T guess. Check the schematic and if you can’t figure it out, ask
someone.
As far as replacing the electrolytic capacitors, you have many options.
Some top chassis aluminum cylinders are available but are very
expensive and hard to find. Usually it is much easier to just install axial
lead caps under the chassis. There is usually lots of room after the paper
caps have been replaced. It is best to avoid using the original can
terminals for connecting the new caps. Disconnect the wires from the old
cans and leave it mounted to the chassis for appearances sake. The
electrolytic sections could short and render your restoration useless.
Remember to use new caps with a voltage rating equal or greater to the
original voltage. When in doubt use quality units of 350V or 450V.
Below are some examples:
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Electrolytic capacitors
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39-25 PHILCO schematic lists
2 of 16 mfd 250V USE 2- 22mfd 450V
38-12 PHILCO schematic
lists
1 of 8 mfd 400V USE 1- 10mfd
450V
1 of 4 mfd 250V USE 1- 10mfd 450V
60 PHILCO
schematic lists
1 of 12 mfd 400V USE 1- 22mfd 450V
2 of 8 mfd 250V USE 2- 10mfd 450V
37-620 PHILCO schematic lists
1 of 8 mfd 250V USE 1- 10mfd 450V
1 of 12 mfd 400V USE 1- 22mfd 450V
40-180 PHILCO schematic lists
1 of 16 mfd 400V USE 1- 22mfd 450V
1 of 12 mfd 400V USE 1- 22mfd 450V
1 of 16 mfd 400V USE 1- 22mfd 450V
A power supply filter can be replaced with one as much as 50% over the
value, but keep in mind much higher could result in increased
transformer and rectifier surge current when powering the set up
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04/05/2012 23.22
PHILCO BAKELITE CAPACITORS: REBUILDING THEM
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PHILCO BAKELITE
CAPACITORS:
REBUILDING THEM
Philco started using the new Bakelite Capacitors in June of 1930 in
their models 30, 41, 77, and 96. These were phased out in the late
1930’s and were replaced by paper capacitors. But the bakelite
blocks were used in the AC line filters as late as 1948.
The blocks consist of a bakelite shell with capacitors wired to
appropriate terminals and sealed with a “tar” or “pitch” mixture and
a single self-taping metal screw, that sometimes also serves as a
chassis ground. Terminals riveted to the top of the shell provide
connections for the capacitors inside the shell. Often extra terminals
were added to serve as tie points for wiring.
The PHILCO Part Number is Hot stamped on the side of the shell
and the very late one’s have a yellow painted part number imprinted
on the side. The letter ”O” in the part number means that it was
filled with a high temperature wax, and letter “G” means the block
is grounded to the chassis, and the letter “U” means that it is
ungrounded.
A paper-dielectric capacitor that is inside of the shell is shown at
the top of this page.
Now a word to the wise that MOST other site’s don't tell you.
SOME of the bakelite blocks have resistors in the blocks
consisting of a hank of insulated wire folded in a figure eight (8)
inside a very small envelope, and 110 and 250 pF paper capacitors.
DO NOT use 0.001 caps, instead use 100 or 250 pF mica capacitors
and the suitable resistor. Most of these blocks start with 8035something.
The VERY FIRST thing to do when rebuilding the blocks is to color
code the wiring with a dab of paint on a touch up-brush and make
a drawing of the block and what wire goes to what terminal. Then
just cut the wire as close to the terminal as possible and remove the
block from the chassis.
I have a small vise shown at the top of the page that I clamp the
block into and a small pocket screwdriver to dig the “tar” out in
chunks. If it will not come out I use a hair dryer to heat the block
up. Be careful the block doesn’t break. Use a small pair of wire
cutters and cut out the wiring of the block inside. Then I have a
jar half filled with lacquer thinner to put the block in to shake
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PHILCO BAKELITE CAPACITORS: REBUILDING THEM
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vigorously, washing out all of the “tar”. Re-clamp it back in the
vise and clean the solder off the terminals and the wiring out of the
eyelets. Take a drill and drill out the eyelet holes. Put the
capacitors and resistors in and the wire though the eyelet and
re-solder it and snip off the excess wiring.
I refill the blocks with a caulking gun and a tube of “DAP”
Blacktop Driveway Sealer. DO NOT use silicone sealer. Put it
into the freezer for about 15 minutes and reinstall in the chassis.
Use the next two (2) pages as a guide for the capacitors
and resistors.
For information on
Metal Case Capacitors
For information on
Tone Control
Capacitors
For information on Multi-section Case
Capacitors and
Electrolytic Capacitors (Big Black Box’s)
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04/05/2012 23.22
PHILCO SERVICE BULLETIN NO.289 1st Page
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PHILCO SERVICE BULLETIN NO. 289 1st Page
How to use this bulletin:
Read the number on the side of the bakelite shell.
Look at the “discontinued bakelite condensers” on
this page, and see if the number was replaced. Most have been!!
Look up the number in the listing, most will be on the
2nd page. Wire and use the value as the bulletin states.
Be careful of the one’s that use 100 and 250pF and
Resistors.
This bulletin does not list 29 bakelite
capacitors:
15 have no information and 14 are not listed
but I have the information, just E/Mail me.
The 15 with no information are:
The 14 that I
are:
3615-BS
3615-BU
8320-SU
3615-BW
8325-DU
4989-AL
8326-SG
4989-AM
have the information The 15 with no information
are:
7442-OSU 8318-F
3615-BY
3793-AK
4989-AS
7653-SU
3793-AF
3793-AL
4989-AT
7762-SG
3793-AG
3793-AM
4989-AU
8035-P
3793-AH
4989-AN
4989-AW
8174-SU
3793-AJ
4989-AP
4989-AY
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PHILCO SERVICE BULLETIN NO.289 2nd PAGE
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PHILCO SERVICE BULLETIN NO.289 2nd PAGE
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04/05/2012 23.23
MY PHILCO STUFF OTHER THAN RADIOS
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MY PHILCO STUFF OTHER THAN RADIO'S
8 + 10 Window card
for radio shop
ca.1935
Full page Newspaper ad, sent to its ca.1929
dealers from PHILCO, Philadelphia
in 1929
RADIO REPAIRMANS
RMS CERTIFICATE
ELECTRIC
CLOCK
ca.
1935
ca.1935
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MY PHILCO STUFF OTHER THAN RADIOS
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WALLET SIZE BUSNIESS CARD
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ca.1935
DEALER WALL PLATE
LIFE BEFORE PHILCO RADIO
ca.1952
ca.1928
Sign hanging in my shop
From December , 1935
PHILCO SERVICEMAN
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04/05/2012 23.24
SCHEMATICS and SYMBOLS:
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SCHEMATICS and SYMBOLS : How to use them.
Schematics are like a road map for radios. Can you imagine driving
across the U.S.A. without a road map? People who have years of
experience with working on radios may be able to work on them
without one, but not for long. When driving you need to know the
road signs and I am going to give you some of them for radios.
There are hundreds of thousands of schematics, and there are 3
major sources for them. Rider started in about 1930, Sam’s Folders
started in about 1948, and the third source was the manufacture's
schematic of the radio. Rider and the manufacture is your best bet.
Rider’s first one is Roman Number I the second is II and so on. I
have from Numbers I to Numbers XIV. I purchased all I needed from
1929 to 1942 for the old Philco’s. Rider’s Roman Number I can get
very expensive, but worth it.
Now you can also get Rider on CD’s but they are also very
expensive. I use only the books. Can you imagine carrying the
computer out to the workbench every time you need something or
taking the chassis inside too use the computer. Only kidding! I just
prefer taking the pages out of the books to carry around rather than
printing from the CD’s.
If you are using Rider, you also are going to need an index for
them. Rider is almost worthless without an index. The index list is
by the manufacture and model, NOT by the year. This means if you
have a Philco Model 95, it says 1-23, which means volume I, page
23 in the Philco section. If you had a Philco Model 37-610, it says
7-45, that means volume VII, page 45 in the Philco section. If you
had a Philco 39-40, it says 10-19 that means volume X, page 19 in
the Philco section, and so on.
The following chart shows SOME
of the symbols used in schematics.
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04/05/2012 23.24
HOW to get PHILCO INFORMATION
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HOW to get PHILCO
INFORMATION
PHILCO SERVICE BULLETINS:
This and 2 more ways was how Philco got Schematics and Service
Information to its RMS members.
The service bulletins were schematics for each model radio.
Sometimes they had other information. For example bulletin
#289 was for Bakelite Capacitors. Rider used these for their
manuals, but PHILCO was a pretty good company and when they
had a problem they tried to rectify the problem right away so there
may be more than 1 bulletin for a radio. For example Model 60,
the first bulletin was number 164 the second bulletin was number
164A. Rider did not always publish the second bulletin.
PHILCO CHANGES IN MODELS:
This was another way Philco let its members know that they had
changed something in their production. They sometimes changed
their production runs as many as 5 times, so you may have one
change in run 2 and another in run 3 and run 4 may have changed
it back to run 2, as in Model 60.
PHILCO SERVICEMAN:
This was published by PHILCO as a little newspaper, with
editorials and discussions about the changes they had made in
production and any new products. Sometimes there were
discussions on why they did things one way and not another such
as in their September 1935 article on why they did not use metal
tubes.
All this seems confusing to present day restoration people, but this
was no problem for Philco Repairmen who belonged to RMS.
They just used the Philco schematic and checked the PHILCO
CHANGES IN MODELS for any changes in the set.
Not all schematics were written the same. PHILCO’S own
schematics were written the same, while others were NOT. YOU
MUST be careful, for example resister ohms, one may say 500,000
ohms and one may say .5 Meg. They both mean the same. If you
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HOW to get PHILCO INFORMATION
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don’t understand ASK someone.
Below is an article written in September 1935, and copied from a
PHILCO SERVICEMAN.
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