Magnavox Micromatic 150927-2

Hi there. New guy here, just acquired a Magnavox micromatic 150927-2. I haven't fiddled with it (much) yet b/c I don't know much about it, but it seemed to work well, was in great shape and was $95, so within my price range. I do, however, have some questions that I'm hoping can be answered.

Everything seems to be in working order (tuner, knobs, speakers, turntable, tonearm...and that other arm that holds additional records...noob, remember?), however, I'm not getting sound from the record. When the needle touches down, I SWEAR I can hear very faint music coming from the needle (hallucination?), but nothing comes out of the speakers, not even static. Now here's the kicker: If I leave the TT on and the tonearm in place, and switch from AUX to PHONO, for a second or two, I can fully hear the record player, and then it fades out (not ends abruptly, but fades). So I know there's sound somewhere in the system, it's just not making it to the speakers when the PHONO position is fully engaged. Thoughts? Could it be stylus pressure? need a new cartridge (EV 26?), needle (EV 26 also?)? Is the switch just bad, or could it be a preamp issue? Do these things even have a preamp?

I imagine someone is going to suggest that I remove the back and fiddle with the flux capacitor while forging new resistor modules, but as I'm sure you've guessed, I'm not inclined in that regard. To some extent, I'm willing to try things, but frankly, I don't want to mess this baby up. So, I'm in the Philadelphia area, can anyone suggest a decent repair/restorer? I want this old girl to work, I don't want a full restoration. I've read on here of a member named MattTech and was going to reach out to him. Anyone else?

Thanks for all the help in advance. I'm really excited about this. The console's in great shape, and I already have records in it. Now I just need to play them. Here's a couple images just for reference.





Thanks! Jake

Jake, you have a similar machine to what I have in my living room. Mine was made in 1965, yours will be too.

What I suspect is happening is that the power switches are malfunctioning. When you switch from any mode to "phono" the turntable then controls power to the receiver. The idea is that when a record ends and the T-T shuts down the receiver will too. If that transfer switch isn't working, power from the T-T will not turn on the receiver. When you switch to aux and back to phono there is a brief period where power remains in the power supply and that is why you hear brief, fading sound.

One point here is that the receiver has a lighted tuning scale and there is a pilot light in the center-bottom front of the console. These should be lit whenever the unit is in use in any mode. If not, they are probably just burned out.

You will need to open the back and if possible, post a pic of what the internals look like. If the receiver is of one chassis design I can point you to the schematics for the receiver.

The plain facts are that the unit is nearly 50 years old and it will need at least to have most capacitors replaced for best performance and safe use. The turntable also needs some care including proper lubrication and possibly a new/better cart.

Rob/NYC

Rob -

Awesome. It sounds like we're headed in the right direction since the light you're talking about is on for every function except PHONO. For my unit, a light comes on in the back, but there's no light in the front. Am I understanding you correctly? There should be a light in the front, too?

I will open her up tonight, snap some pics, and get those up. And I'm ready to try my hand at capacitor replacement and making this thing work the best it can. Worst case scenario: I learn something! It'll be interesting to see what the internals of this old girl look like. The switch b/w the TT and the receiver, is that something that will be plainly obvious? Either way, looking forward to it.

Thanks for the ongoing help, Rob, and anyone else.

--Jake

I got the back off of the old girl and had a poke around. About 50 years worth of dust, plus I found the missing screws that hold the back board on, so I got that going for me, which is nice. Here are some pictures for your viewing pleasure. If anyone sees anything that looks familiar, please point me in the right directions (how to clean, how to replace parts, where to get those parts, etc.).

In the meantime, I'm going to go have fun with the search function to see what I can learn.

Thanks!

Jake, I have good and, well, not-so good news.

Good is that you have one of the deluxe models and I have most, if not all the schematics and service data for that one.

Bad is that the switches in contention here are located in the tuner-control unit and that has to be removed to get at them.

This involves removing all knobs. Carefully removing and tagging (and diagramming) all plugs...and then the fun part; that chassis is held by four bolts that go through the wood mounting platform and into the sides of the chassis pan. So those must be carefully removed and the chassis held as you remove the last one so as not to let it fall while also not holding it in such a way as to grab something that might break off (the AM antenna).

If you still want to deal with this, I suggest you tighten the hold down bolts on the turntable 9just hand tight) remove the two sliding doors and tip the whole unit on it's side with the radio-control unit upright. this way atleast you can more easily remove the bolts w/out danger of it falling.

Before doing any of that try turning on the phono mode and wiggling the whit plastic plug that goes into the turntable assembly. It is the one with Red-yellow-Black wires. It it possible that the pins have developed resistance and not allowing power to the receiver...a faint but worthwhile try.

I'll scan some of the data later. meanwhile, now that you've peeked inside, you need to assess how much want to deal with yourself. This is old-school tech and -most- voltages inside are harmless...to you...but transistors are not forgiving and a mistake can be costly and destroy semiconductors instantly.

Rob

Rob - thanks for all the great direction. I can manage to wiggle some things, and once i get a look at those schematics, I'll see how much of this I'm willing to tackle myself. I was good to dive in myself until the part about destroying semiconductors instantly. I'm not worried about my own safety, simply the safety of the unit.

Overall, I'm excited to take a deeper dive and get my hands in there. Again, don't want to damage the unit, and perhaps once I'm elbows deep I'll realize I've gone too far, but worst case scenario is I learn a few things, which can't hurt. At that point, I'll close her up and find a technician.

Again, appreciate the help, and thanks for scanning those documents. FWIW, I'll PM you my email address in case it's easier to send them my way than post them here.

Thanks!

--Jake

Ok, here are the schematics for th tuner-control unit:

http://www.fileconvoy.com/dfl.php?id=gb ... d5fadd5fe9

http://www.fileconvoy.com/dfl.php?id=g0 ... af1cdccd4b

http://www.fileconvoy.com/dfl.php?id=g0 ... ffb52fe108

http://www.fileconvoy.com/dfl.php?id=g5 ... c8f6a99406

These are actually one long page which didn't fit the scanner, so I broke it into four pages. There is overlap and it will probably be easier if you print them out and cutoff the overlap.

Chassis: http://www.fileconvoy.com/dfl.php?id=gc ... 420c9be591
& http://www.fileconvoy.com/dfl.php?id=g1 ... 82b4bfc74c

I'll send some additional material when i have time later.

Rob

Wow, from the looks of that, it appears to be some type of Astro-Sonic 100. I have several smaller units in the camp, but those AS 100's take music to another level. I paid $25 for a Santiago, having no idea what it was, and stacked it on in end with the other five or six back in the spare bedroom before buying my house.

When I finally unleashed the Cracken, I was completely blown away. The smaller units are already impressive, but those 100's have a flavor all their own.

Oh, that bottom picture has a "CHASSIS" date sticker on it. It looks like July, 1964 or 1965. --BB

Bobby Basham
Tucson, Arizona

I just bought a Micromatic Console Ebony, Osaka, model # 1RP638
Serial # 6144717
Everything works but there is no needle/stylus number. As far as I can tell this particular model came out in 1966.

Everything seems to work but I'm betting that the turntable will need some work and I'm a little concerned that the auro record drop may not work. The turntable spins and the radio works but when I turn it to FM Stereo, I only get sound on one side???
I bought this for my 19 year old. I'm thrilled with the sound! He is hoping to get it working.
Any help is much appreciated!
Mom