Meet my friend Rusty the Fisher KM-60 Tuner

Both fuse lamps show open. Anyone have thoughts on whether I should source new fuse lamp bulbs or go LEDs? If I go LEDs can I get enough candle power?
 
I get fuse lamps from wjoe.com. They work quite well in the tuners, and receivers. You can also get LED Fuse lamps from him. About the only units I have LED's in are my Sansui 1000A and my PIONEER SX-434, 737, and 939. They look better in these. The FISHER's I like the incandescents.
 
Larry,

The pic that looks like mine are rated at 13V. Does that sound right?


Festoon
13v
.38A
DE3022
 
I get the 12v Fuse lamps and if the unit has the extra long lamps, I'll bust one up per side and solder the end caps to the lamp to get length. the DE3022 look like they might work, but check the holder length 1st. The AG3's I get usually a pack of 10 and bust 2 up for each unit for the end caps. Unfortunately the KM-60 uses a 6V bulb, so you'll either have to find a 6V festoon or do a Fuse lamp/LED. The GF650 works well but may need one or two end cap extensions. I can't remember as mine is still in storage. And the meter lamps are #470 6V screw in's. A #46 may be a sub. Also a #240 but I'd check the amperage of the 470 and compare it with the 2 and get the closest without going over the #470's amperage rating.
 
Thanks Larry.

You are right the KM-60 lamps are 6V. Before I saw your post I did some checking on the schematic and these lamps are in parallel with the filament heaters which are 6.3V (nominal). That gives me the information I need to start shopping around.
 
Continued to clean the dial glass, restrung the dial cord which was originally installed/routed around one of the pulleys incorrectly (probably been that way for 50 years). Cleaned the knobs up and started looking for festoon bulbs for lighting the dial. I also am looking for a knob bright which is missing for one of the knobs.
 
Alignment tools and decals for the missing stenciling have arrived.

Also picked up some felt pads to hold the dial glass with the metal tabs that it came with and some foam weather strip to block the light around the dial glass from escaping.

Sorry there haven't been a lot of pics. I'll add some soon.
 
Saw this one late.

OP, do yourself a huge favor and check those IF cans before you put too much elbow grease into this one.

With that much surface corrosion, I would be very concerned about moisture damage to those internal film micas. They sit at the can bases, right near that rusty chassis. Once wet stuff gets in and eats ‘em up, you either have to break down the cans and install new discrete micas, or source replacements. Neither one is a fun prospect. Lots o work on what is already a project case.

And the earlier comment about frozen cores is legit as well. You can’t tune an IF stage if the transformer core is welded in with corrosion.

A shiny waxed chassis is small consolation for a tuner that can’t be aligned.
The can thing killed two Fishers and a Dyna FM-3 here, I avoid vintage FM tuners as a matter of course now since I cannot align them after fooling with the IF can thing.
Nice save nonetheless, your effotef and results are edifying.
 
Well, I've finished initial cleaning - including the dial glass and I've reassembled the dial and faceplate. Looking pretty good. Next is to check those IF cans and then maybe - just maybe... Bring it up on the variac.

I've got decals to replace much of the missing stenciling. I'll start with the V numbers and add in the tube types below each. The alignment tools I bought are not the right kind. The ends are too small. It must be for later TV alignments. It seems I need two types. A hex type and an rectangular type. Anyone have any ideas?
 
This should suit your needs just fine:

https://www.ebay.com/itm/Universal-...soAAOSwMrBaegB9:sc:USPSFirstClass!30107!US!-1

I have no connection with the sale of this product - it just appears to offer the tools you need. If they don't work, check that the slugs have not been damaged by the use of inappropriate tools, making the tool fittings in the slugs too large now for the proper tools to work.

Dave

Thanks Dave,

Looks like the hex end of the red one might be one of them. The other end of the red one might be the rectangular end I need too. I'll go order those and we'll give it a shot.

Thanks again for your invaluable inputs. :bowdown:
 
So I'm making some progress in getting ready to power it up. I'm very close to doing that.

The unit is 98% cleaned up. It's all assembled except for the bottom plate and installation of the tubes. It's almost ready to power it up on the variac. There is some rust inside the chassis and on the bottom plate, but I'll save that for final cleanup. I've been replacing the missing stenciling on top of the chassis with model railroad decals (3/16"). The characters are a bit big, but my hands can't work with anything smaller. I'm definitely not an artist, but this will go inside a nice wood case, so very few will know. It doesn't look great, but it isn't too terrible either. I'll take some pics of it soon.

I won't check for free movement of the IF can cores until the new plastic alignment tools arrive. I'll proceed with the following without doing that step.

Tonight I'm going to check continuity (in-circuit) of the IF cans with a digital multimeter (not a VTVM). I'll be watching the diagrams to see if I can tell if there are any parallel circuits that invalidate that plan. After that I'll install the tubes and bring it up slowly on the variac and check voltages. Fingers crossed. It remains to be seen if it needs an alignment or even if it will be operational without additional work. Now the real fun begins.
 
The Front End came from the factory aligned of course, as did the MPX section, and the pre-alignment done on the various IF transformers was usually quite good. Now it somebody has played with it, then all bets are off for any of it, but hopefully, that won't be the case.

Good luck with it!

Dave
 
Thanks yet again Dave....

I didn't get too far this evening because the wife wanted to go shopping, but I got the tube tester and variac out and tested a full set of tubes for it. After that I called it a night.
 
Got a knob bright coming tomorrow for one of the knobs. Also the alignment tools should arrive tomorrow as well. Just love that the number of tasks is getting shorter.
 
Knob bright installed. Had to pull and insert, and rock some of the tubes before both sides (of two sided tubes) would light. I eventually noticed that the signal strength meter would move in some areas of the dial. That was exciting as I hadn't done any repair other than re-capping, replacement of the bridge and fuse holder so far.

I checked the IF cores and they seem to be movable. Today I started powering it up on the variac and found I'd made a couple of wiring errors when installing the new multi-cap and fuse holder. Corrected those and got serious about powering it up. Got it all the way to 115V. Actually hooked it up and I'm getting 3 stations in mono only. For now I'm just using a couple of alligator leads as an antenna. Found some new problems.

1. The dial is backwards. Increasing station frequency is actually down the dial. I'll be checking the dial cord, but I think I've got it installed correctly. Hope the tuning cap isn't screwed up or dirty.
2. Only getting sound out of the right channel in Mono. When I switch to Stereo there's no sound. Maybe I should continue cleaning and re-tensioning the sockets?
 
The only way the dial can work backwards is if the dial string is installed incorrectly -- nothing electrically will do that. In essence, the tuning cap is turning the wrong direction relative to the dial pointer.

Make sure the Stereo/Mono switch is clean, and that all tubes are lit. The KM-60 has plenty of sensitivity, using Fisher's best (in my opinion) front end, marketed as the Golden Cascode. Plus, that front end in my experience has virtually zero drift to it. The MPX section has to have something seriously wrong for it to not pass any signal at all. It, and the RF section are the two parts of the tuner that were factory built.

Dave
 
The only way the dial can work backwards is if the dial string is installed incorrectly -- nothing electrically will do that. In essence, the tuning cap is turning the wrong direction relative to the dial pointer.

Make sure the Stereo/Mono switch is clean, and that all tubes are lit. The KM-60 has plenty of sensitivity, using Fisher's best (in my opinion) front end, marketed as the Golden Cascode. Plus, that front end in my experience has virtually zero drift to it. The MPX section has to have something seriously wrong for it to not pass any signal at all. It, and the RF section are the two parts of the tuner that were factory built.

Dave

Thanks Dave,

I'm checking the dial cord. I'm not seeing a mechanical problem with how it is strung in comparison with the assembly manual. I did find a funny mistake in the way it way it was stung when I received it. I corrected that mistake with the help of the assembly manual. I'll keep looking at it. Maybe I'll have an epiphany.

I just powered it up and was gratified to get anything out of this unit considering the condition it was in when I received it. I'll start cleaning switches and sockets to make sure that everything is properly lit and connected.

I will say that the 3 stations that came in as Mono sounded really nice. That's a good start.
 
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