0:07 hi welcome to another edition of antique
0:09 radio archaeology today we're going to
0:14 do a restoration on a montgomery wards
0:18 airline brand mini radio and this thing
0:20 was produced in 1940
0:24 and it goes by the model number 04 br 511a
0:26 511a
0:29 now i picked this thing up off of ebay
0:32 about 11 years ago and i've spent quite
0:34 a bit of time over the years just
0:36 intermittently doing a little bit of
0:38 research on it
0:39 and it was tough
0:41 and let me tell you why
0:44 because this particular model has
0:47 has
0:50 a model number that goes right here
0:51 on this chassis
0:53 that's missing
0:57 and so is the sticker on the bottom so
0:58 so
1:01 what that has done is it's caused me to
1:02 have to
1:05 figure out what model i had now this
1:08 particular radio was produced in
1:11 four different years in 1940 they
1:16 produced an 04br 511a and a 512a
1:19 the 511a is the brown bakelite version
1:22 you see here the 512a is an ivory version
1:24 version
1:26 later in 1941
1:29 they continued producing the same radio
1:30 but they changed the model number
1:33 instead of it being an old 4br it was a
1:37 1 4br for 1941
1:39 and they also had the 511 a and b for
1:41 brown and ivory no circuit changes no
1:43 nothing it was just a model number
1:45 change and that was the beginning of 1941.
1:47 1941.
1:50 towards the middle to end of 1941 they
1:52 introduced a
1:56 new version of it it had a different
2:00 dial glass or plastic i should say
2:02 on it which was a little more ornate it
2:05 had kind of a gold surround on it looked
2:06 really pretty
2:09 and inside they actually switched over
2:14 from the 35 l6 gt output tube
2:18 to the 50 l6 gt output tube and when
2:20 they did that they also eliminated the
2:23 filament resistor because obviously the
2:27 50 is going to take a little bit more uh
2:29 power so uh
2:31 by eliminating it the
2:34 power it needed to function obviously we
2:36 all know that in 1940
2:38 one was pretty much the last year they
2:41 were making a lot of consumer grade
2:44 radios because of the war
2:47 so in 1945 they came back with another
2:49 version of this radio and it was the
2:53 54 br for 1945
2:57 and they changed the last digits to 1501 a
2:58 a
3:01 and 1502 a for the brown and ivory version
3:02 version
3:06 now on the 1945 version they did some
3:09 minor uh tweaks on the circuitry
3:11 um the dial
3:15 glass changed to one with larger numbers and
3:16 and
3:18 they also
3:22 reintroduced the filament resistor a
3:26 smaller one in the 1940 version
3:27 version
3:29 it was using a
3:30 50 ohm
3:34 resistor they eliminated it in the
3:36 1941 model year
3:39 and then they brought back a resistor
3:42 only it was a 33 ohm so obviously the they
3:43 they
3:45 probably figured out that it was drying
3:47 a little bit too much
3:49 so uh in
3:50 in
3:52 1946 they really didn't do anything
3:56 different there was no additional model
3:58 but 1947 they came up with the last
4:02 version of this and that was the 74br 1501
4:03 1501 b
4:04 b
4:09 and 1502 b for brown and ivory and
4:10 and
4:13 that one had the same dial as the 1945
4:14 the only
4:16 big difference and that was a big
4:18 difference was a lot of the circuitry was
4:19 was modified
4:20 modified so
4:21 so
4:24 the hard part about this whole process
4:26 was trying to figure out what exactly
4:28 did i have you know
4:30 there were so many different variations
4:32 so i had to pretty much
4:34 get the schematics for each year and
4:37 compare them and finally determine that
4:41 this is either a 1940 or 1941 early model
4:42 model
4:44 with that being said
4:47 i now know what i need to do to restore
4:51 this radio so let's go ahead and
4:52 open this thing up and
4:56 get into a little bit more of how this
4:59 thing was so unique at the time it's
5:00 really amazing some of the things they
5:02 did in order to miniaturize it
5:04 let's go ahead and get this chassis out
5:52 as you can see this has some full-size
5:54 tubes in it's pretty uh
5:56 i mean they're i guess they were small
5:58 for the time sort of
6:02 but uh they're definitely bigger than uh
6:04 tubes today and
6:05 and
6:25 now this thing was in pretty rough shape
6:26 when i got it
6:28 11 years ago
6:31 i did clean it up a little bit
6:35 as far as the chassis and
6:37 the case here so
6:38 so
6:40 definitely don't have to do this during
6:41 this restoration
6:43 but here you have the tube complement
6:50 a 12 sa7 right here that goes basically
6:52 to the antenna circuit and then you have the
6:54 the
7:00 12 sq7 which is the detector 12 sk7 over
7:04 here which is the if amplifier
7:07 and then you have a 35
7:11 z5 gt which is the rectifier tube
7:14 and over here is your output 2 which is the
7:15 the
7:19 like i said before the 35 l6 gt and in
7:23 other models that would be a 50 l6 gt on
7:25 top here we have your
7:27 your
7:29 electrolytic capacitors which those are
7:32 going to have to be replaced obviously
7:37 see it's all warped
7:39 that's that face plate
7:54 as you can see we've got
7:56 our work cut out for us
7:58 now here's some of the uniqueness of
8:01 this radio that i wanted to point out
8:03 okay here's the tuning
8:06 now as you can see
8:08 as i'm tuning it there's some rods i
8:10 don't know if you can see the one back
8:12 here or not
8:15 but there's rods going in and out
8:17 these two coils
8:20 and that's your antenna tuning section
8:23 very very unique i really like that
8:26 down here we have a lot of
8:28 got some blown uppers
8:30 capacitors here you can see the ends
8:33 blown out of that one that one
8:35 the cord of course the electrical cords
8:37 cut off right there so i'm gonna have to replace
8:38 replace
8:41 six capacitors which are here here here here
8:43 here there
8:49 so i got one two three four five six
8:51 those six so i'm gonna go ahead and
8:54 replace those first and then you can go
8:56 from there
9:00 on the back here you have this uh
9:01 connection here that's your antenna connection
9:03 connection
9:06 and it hits the back of this plate
9:08 when that's screwed in and then you
9:11 attach your antenna to here so
9:13 so
9:16 basically your antenna hits that
9:18 capacitor right here
9:19 before going into the antenna section
9:21 it's using this back plate as a capacitor
9:23 capacitor
9:26 okay so in preparation for
9:27 this restoration i went ahead and got a
9:30 power cord to replace the one that was
9:31 cut off i went ahead and drew out the
9:35 capacitors and the values that i need
9:37 and i went ahead and identified them
9:38 from the schematic
9:39 all right
9:43 i went ahead and got my electrolytics
9:45 already now remember the electrolytic capacitors
9:47 capacitors
9:48 are built into
9:50 into here
9:51 here
9:53 and what i've got is a
9:55 a
9:57 40 microfarad and a 20 microfarad built
9:59 into that so
10:00 so
10:03 to replace it what i picked up was i've
10:06 got a 22 microfarad and i'm going to go
10:09 with a 47 microfarad for the 40.
10:11 so that should work i always like going
10:13 a little higher if i don't have the the
10:20 so that's it that's my six capacitors
10:26 okay just to make things a little
10:28 simpler what i've done is i've
10:30 identified which capacitors i'm
10:33 replacing it's going to be c4 c6
10:35 c6
10:37 c8 and c9 are those electrolytics i've
10:42 got a c10 c12 14 and 15.
10:44 so those are the capacitors and this
10:47 tells me where they're hooked to
10:48 okay so
10:51 one of the issues that i ran into was c15
10:54 c15
10:56 which is right here
10:57 is hooked between
11:00 pin three and pin four on this tube socket
11:01 socket
11:04 which is the output two it is not
11:06 in the schematic hooked between three
11:08 and four i checked the other schematics
11:10 for the other models it's not hooked
11:13 between three and four on any of those
11:17 so i really started questioning what the
11:19 validity is the schematic and then i
11:22 went and found a couple of these online
11:24 that showed the bottom here
11:27 and what i was able to determine is this
11:30 capacitor's hook between pin three
11:34 and this first lug on r6
11:36 so i followed this
11:39 boom boom boom come down
11:42 over to here up to here and there it is
11:44 it's hooked to that lug on r6
11:46 on the schematic
11:49 so this is a this is definitely wrong i
11:51 don't know if somebody
11:54 tried to fix something and replaced it i
11:55 don't know
11:56 but whatever it is i'm going to have to
11:58 correct that
11:59 but other than that all the rest of
12:01 these are hooked up correctly i did
12:02 check that
12:04 and i'm going to go ahead and replace those
12:12 so what i did was i went ahead and drew
12:14 some leads here to show where these
12:16 capacitors were hooked i'm going to the
12:18 rheostat here
12:20 with these two capacitors i'm going to
12:21 that switch
12:23 on this real stat which is from this capacitor
12:24 capacitor
12:26 i've got these two pins here that these
12:28 are hooked to
12:31 same here every one of these capacitors
12:32 i know where they're hooked
12:35 based on this little drawing so
12:37 i can go ahead and use that to do my recap
12:39 recap
12:41 which will make things a lot easier so
12:42 now i can go ahead and cut these out and
13:44 okay well that one looks rough shape
13:46 all right
13:49 so i just got one left that's that one
14:05 okay so
14:07 i'm working on trying to get this
14:09 electrolytic out and what i found out
14:11 was i got a
14:13 wire here that's in pretty bad shape
14:16 so as i've discovered that wire that's
14:17 busting apart here
14:20 goes all the way into this can right here
14:22 here
14:23 so i've got some issues i'm going to
14:25 have to get to that can
14:26 i'm going to have to replace the wires
14:28 in that can so
14:29 this is getting a little more
14:32 complicated as we go along so
14:35 all right so i've had to cut all these
14:36 wires i went ahead and marked where
14:40 these colors go on my diagram
14:42 for these
14:45 transformers so what i've got to do is
14:47 i went ahead and unscrew this i already
14:49 got the other one out
14:53 just need to pull that through there
14:54 there
14:56 got them out
14:58 now as you can see these things got
15:21 there we go so i got to replace those wires
15:23 wires wow
15:25 wow
15:26 all right so i'm going to go ahead and uh
15:27 uh
15:29 replace some wires here i'm just going
15:31 to use i have some
15:32 i don't have any of the colors i need
15:34 but oh well
15:37 i i marked on the
15:39 on my sheet there what which one's what so
15:41 so
17:55 so i am in the process of reinstalling
17:58 this can
18:01 i got the wires fished up through here it's
18:02 it's
18:24 route these wires where i need to
18:26 and then we'll get this other can
18:27 installed on the other side and get
18:33 all right so i've been able to secure
18:47 back over to here
18:49 and here
18:51 i've got the what used to be the brown wire
18:53 wire
18:54 route it over to here where it needs to
18:56 be and it's all wrapped on there i
18:57 haven't soldered them yet i'm going to
19:22 okay
19:25 i'll leave that wire up for now
19:37 this one's a lot easier than the other
20:03 it's a nifty little tool here you just
20:05 mash it over the
20:07 nut and
20:08 it grabs it
20:26 okay so i've got
20:30 all these cables from that ifcan
20:34 routed and put in place i've got one
20:37 here one here here
20:39 one that goes back to there
20:42 and one that goes right there so i need
20:44 to solder those i also since i've got
20:45 this uh mica
20:47 mica
20:49 capacitor back in place i need a side of
20:51 those wires that i took off earlier
20:53 so i'm just going to get all those
21:32 the next little step here
21:34 uh i need to hook up this wire i need to
21:37 hook up this wire these all went to
21:39 that capacitor
21:41 that electrolytic capacitor which was
21:43 actually two capacitors
21:45 so what i've got is there's this little
21:50 and i had one
21:53 two little lugs here and i had this lug
21:55 here this is the negative side of those
21:57 two capacitors
21:59 this is the positive side of the 40
22:01 microfarad this is the positive side of
22:03 the 20 microfarad capacitor
22:05 so what i'm going to do
22:08 is i picked up one of these
22:12 i'm going to install that
22:13 down here
22:14 over that
22:16 little nut
22:19 and screw for that if can now this is
22:21 not hooked to anything it's just a lug
22:23 but these three here that leaves those
22:26 three lugs standing
22:28 that's going to allow me to put these
22:31 two filter capacitors the 47
22:33 and the 20
22:34 right there
22:37 tie those to the negative
22:39 and those to the positives and then i
22:42 can hook these wires to this
22:45 instead of down here
22:48 and pretty much create the same
22:51 uh electrical connection so i'm going to
22:52 go ahead and
22:54 pre-solder this i'm gonna put the
22:57 capacitors on here and
22:59 the resistor between them by the way i
23:02 did go in and check all the resistors
23:04 and made sure that every one of them was
23:07 reading within specs and they are
23:11 so let me go ahead and do that real quick
23:17 okay so here is my
23:19 two electrolytic capacitors the filter
23:24 capacitors and that resistor r3
23:27 all tied together on this
23:41 all right so that's going to get mounted
23:46 with that screw and that
23:48 be placed right in there and then i can
24:52 so i'm totally recap now
24:56 i've got all six capacitors
24:59 one two three
25:00 four under here
25:02 five and six
25:05 i've got the two electrolytics
25:08 i went ahead and uh kind of went through
25:10 it made sure that all the wiring wasn't
25:12 touching anything and none of the other
25:14 components are touching i measured all
25:16 the resistors
25:18 made sure they were all in good shape so
25:20 i should be in good
25:22 shape now to go ahead and install the
25:24 power cord
25:26 okay so
25:29 just got the power cord installed
25:35 got it hooked over here to the switch
25:39 and pin two on the rectifier tube
25:40 so now we should
25:42 kind of checked everything made sure
25:45 nothing's touching anything else and
25:46 and
25:48 let's go ahead and get a dim bulb tester
25:50 and fire it up okay so here comes the
25:53 moment of truth
25:57 always the scary moment
25:59 got my dim bulb tester hooked up let's
26:02 go ahead and
26:10 i don't see any
26:13 any light on the
26:33 what's interesting is i don't have an
26:38 here's the up
26:49 when it comes to the
26:53 issue he's thinking about this
26:55 well i got two two stations without an
26:59 antenna i can't complain about that
27:01 well now we know it works
27:03 so there's a couple things i need to do
27:05 here uh the speaker itself has a couple
27:09 little tears in it it's just
27:10 very slight but
27:14 i i can cover that with some glue and
27:17 help to hold that together
27:19 okay so what i'd like to do is a real
27:22 quick uh speaker repair
27:24 you may not be able to see in the camera
27:27 but there's a hairline crack that runs here
27:29 here
27:31 that way that way and then there's a
27:33 little spot over here that's
27:35 that's busted through and
27:37 and
27:38 looks like
27:40 right there too is a little bit
27:42 so what i'm going to do is i'm going to
27:43 mix a little bit of white glue with
27:46 water it's about a one to one ratio
27:49 so let me just squeeze out a little bit here
28:02 push that on there
28:20 and what i'm going to try and do is get
28:22 the back side which i don't think you're
28:23 going to be able to see too well from here
28:31 let that dry and
28:37 so while we're waiting on the glue to
28:40 dry i went ahead and printed up some
28:52 okay now the reason why i know the
28:55 dimensions of this thing is because the uh
29:04 you can kind of see where the label was so
29:11 it's gonna go right there [Music]
32:31 well i hope you enjoyed today's episode
32:33 it was definitely an adventure for me
32:36 because uh i've been wanting to restore
32:37 this thing for
32:40 gosh 11 years now so finally got around
32:43 to it glad i did and it was definitely a
32:44 learning experience i can't believe how
32:47 compact everything was in this thing and
32:50 how hard it was to get in there and do
32:52 the work that needed to be done
32:55 but it's all done i do want to do an
32:57 alignment on it at some point but uh for
32:59 now it's uh
33:02 it's good to go i
33:04 will probably just be putting it on my
33:07 shelf and listening to it when i can
33:09 in the meantime i hope you enjoyed
33:10 today's episode
33:12 if you did please hit the like button if
33:14 you'd like to see more episodes like this
33:15 this
33:17 please hit subscribe if you haven't
33:19 already done so in the meantime happy
33:22 restorations everybody hope you have a
