New Guy w/Questions about OLD Motorola Gear

[W3OSS]

Hi Gang:

I am new to this mssg board. It was suggested that I ask nicely on this board about information concerning converting a couple of D41GGV low band FM units to either 6 or 10 meters. I picked these two radios up about 3 months ago with the intention of putting them on 6M. However, I think it might be better to put them on 10M (less work). I also wanted to add the components for a second channel, since the chassis is already punched for the parts.

These two rigs have QC tags date 1958 but they are in terrific shape internally. They came out of Civil Defense use probably 20-30 years ago. I need mics, schematics, and some kind of test set with cables to align the units after xtals are swapped out. Currently these units are on 33.80MHz. From what I understand, I will pobably need to drop the deviation down since these were originally set up for 15kHz deviation, if my info is correct.

So, anyone out there in BatLab-Land able to help me out?? If so, pls reply directly to me to keep the bandwidth down on the board.

73 Rich Arland, W3OSS

[Will]

The D41GGV radios came in four 'splits', 25-30, 30-36- 36-42, and 42-50 mhZ. If yours is a 30-36, it should tune down to 29.6 without any problems. Most of these were 'narrow banded' for 20 khz channel spacing and +- 5khz deviation.

I worked on lots of G series in my days, too....

The mic is the same as used on most mobiles up to and including the Motrac/Motran and Mocom 70 radios, 4 pin Amphenol connector.

[WB6NVH]

The TU546 test sets are on eBay frequently, inexpensive as a general rule.

The 30-36 G strip radio tunes to 10 Meters without modification. Trying to move it to 6 Meters is a large amount of work.

Be aware that G series receivers, now 50 years old, may have a bad Permakay filter, and you may be making one good radio out of two if so. Also that crystals are rather pricey these days. And that the vibrators will probably need replacement and possibly the selenium rectifier bank. Finally, expect a few weak or bad tubes.

Adding a second channel requires the oscillator coil/s and the coil shield shells. There was a kit for installing the coil shields which consisted of a die and anvil kit which you used a hammer with to seat them. Not exactly a common item today.

[GlennD]

The biggest killer is that the cotton covered rubber insulation will turn to dust if you move the wires!

[Will]

What a flash-back.. we saw a D43GGT in the railroad configuration at the local Ham swapmeet last saturday. Mike has a couple of photos.

[WB6NVH]

I should add that most of this gear has already been narrow banded even though it may have started out life as a 15 KHz radio. There's a round paper sticker on top of the electrolytic can capacitor on the transmitter strip which will tell you what standard the radio is. The transmitter in that model was made narrowband by just turning the deviation down! A lot of agencies were buying narrow banded radios already in '58 even though the rule didn't become mandatory until 1962.

If the receiver is narrow banded, the Permakay filter will be marked TU-540S. TU-540W is wide band. But, either will work on 10 Meters and you won't notice the difference.

You should be able to get about 0.3 microvolts or better on 29.6; these receivers are quite sensitive.

I still maintain a small fleet of high band 1956 production Twin-V mobiles for the Maritime Radio Historical Society people, which they use for intercoms between the transmitter and receiver sites and in the service car. Some of the gear is 6 volt for a 6 volt Willys. Surprisingly reliable, about the only thing needed is a vibrator change every few years and maybe a new 2E26 and/or 6146 depending on who's been talking too much... Somehow that is a lot more fun than talking on the latest handhelds...

[Tron]

IIRC, weren't the PermaKay filters supposed to be warranted for "life"?

Tron..who has replaced a few of them in his life.

[PETNRDX]

Last I heard the Permakays were still "unconditionally warranteed for life".
And it seems to me that someone on the board actually got a new one in the last couple of years.
Looking at the manual for the trunk mount (T41 GGV) the wide might be the TU 145, optional "narrow" is the K-9240 (looks like a stack of shotgun shells) and the "Tri-K" option was the K-9242 (looks like three shotgun shells).
I recall years ago that we made those (and the T43 & T44) radios "multi channel" by just using very small relays to switch crystals around, rather than adding the coil/cap/tube circuits.
At the time the crystals were stable enuf for ham use.

[WB6NVH]

Good question...the last time I got a Permakay under warranty was in an HT-200 in 1980, and they first tried to charge me $ 200 for it. I wonder how you would even go about making a warranty claim on one these days. I wonder if I saved that coffee can full of bad ones...

He said the D41GGV's were '58 dated, which should be about the time the second generation G strips with the single plastic resin filled Permakay were in use, but that's a good point about the earlier Unichannel G's having the individual cans showing on the filter, and different numbers.

[xmo]

GGT, TU-540S, HT200 --- ahhh --- the gold old days of two way radio.
Speaking of that here's a picture of WIll working at his bench back in the day..
Who would have thought he came over from the dark side?



OK, so it's not a picture of Will.

It's actually the cover photo from the January 1965 issue of 'Electronics Technician' magazine.[found it at a hamfest]

The fellow there is shown at one of GE's bench positions at Lynchburg. Starting pay in those days for EE's was about $600/month. Techs were probably closer to $400

For that you got to work on all kinds of cool stuff. Of course you got your fingers burned on tubes and crystal ovens but in return you go to hear the hum of vibrators, the whir of dynamotors, and the whine of T-powers. And don't forget the smell of a burned up selenium rectifier stack.

Good old days --- or so they tell me.

[Tron]

Don't forget the rectifying vibrators on the 80Ds. In all my years, I never had a selenium stack fail. Must have been luck. Think I still have a dynamotor or 2 laying around.

Tron

[arlojanis]

The rectifiers smell like rotten eggs when they get very hot and they start to bubble.

[Glen W Christen]

If you replaced a selenium stack (Yes, they STUNK) with silicon diodes, your power about doubled. I remember when we had to install a 100 W dynamotor (Model 140 D) in the "trunk" of a Pinto. There was no room for anything else, and you wanted the engine well wound up before you hit the PTT.

[jackhackett]

I think I've got one of those signal generators.. and the VOM... and the test panel next to the radio.. and that meter on the top shelf.. dang I'm a pack rat!

[ldanna]

I still have that Die and Anvil if you decide you need it. I remember dual channelling and old 41V with it.
LArry