Fusing Mag. Concert Grand

[ladyk]

I have a Magnavox Concert Grand from 1960. Recapped it and replaced electrolytics and out of range resistors. But I haven't fused it yet. I need help figuring out what sizes, and where to place. It has the Phantom remote and FM multiplexer. Great unit I bought for $20 at a thrift store in '96. I never knew quite how cool it is until not so many years ago. Any help is very much appreciated!

 

[luxflairguy]

What are you talking about? Don't understand

 

[DADoES]

 
Console stereo/radio.

 

[ladyk]

The CG has 6 chassis and 44 tubes but no factory fuses were installed back in 1960. So there is no protection. So I'm needing to add fuses where appropriate. To be honest, I'm a parts changer. I've had mostly success in just replacing the most likely bad parts. I learned how to discharge caps, and read values, but I'm not expert in reading schematics. (I can with time and patience lol). Don't want a catastrophic failure.

 

[cfz2882]

I'say try a main fuse of 3a for the whole unit,2a for the amp transformer,1/2 amp for any small transformers and see how that goes how many output watts is this supposed to have?

 

[delco1946]

This is my dream console...but my house is full of radios and phonos that I think that ship sailed. I don't really hear of people fusing antique stereos, and I've never had any issues after replacing the caps.

This is no normal set - only doctors and the wealthy could have afforded these in the late 50s. The most basic radio had 5 tubes, ~9X% of record/radio combos would have 6-11 depending on quality. Concert grands had 40+ (unparalleled) and could heat a room lol.

Current inrush will be highest immediately after turning on the set when the caps have no stored charge. If not sized correctly I imagine the fuse might trip during warm up. If youre going to the trouble to fuse it you might want to look into other things too such as a voltage regulator depending on your power supply. Most sets where designed for 115-117 VAC and some utilities provide closer to 125-130 VAC these days resulting in sets running "hot" which can stress a components depending on factors. That being said, i've not had any issues after re-capping - the electrolytes being the most critical. in the 30 and 40s some sets had "death" caps. If this set has those (my death cap experience has been with 1940s philcos) i would replace with special caps that fail open rather than shorting, otherwise you probably dont have much to worry about.

I would ask this question at Antique Radio Forum as a misstep could cause damage to an irreplaceable set. Lots of antique radio and record player knowledge there.

 

[delco1946]

Can't edit...but as a "take away", i wouldn't honestly bother to fuse but whatever helps you sleep at night . If you do fuse, ive only heard of a single fuse at the plug/before the power transformer....IMO less is more - ive had great success mucking things up by going overboard but once again ask on the radio forum.

 

[ladyk]

I agree that sometimes less is better. I may get an Elmenco fused plug. It has a fuse on both sides. Hard to find but I see them in eBay, as well as electric fence supply websites.

This will certainly heat a room! The phono compartment would feel like an oven after a couple hours playing. Probably why it went through two idler wheels in 15 years. I fixed that problem. Went to the computer shop and bought 3 12x fans with a power supply. I installed one for each amo, and one for the tuner. I managed to install them on the back without altering it, other than some new studs and spacers to extend the back slightly. Runs cool if left on all day now!

 

[ladyk]

I agree that sometimes less is better. I may get an Elmenco fused plug. It has a fuse on both sides. Hard to find but I see them on eBay, as well as electric fence supply websites.

This will certainly heat a room! The phono compartment would feel like an oven after a couple hours playing. Probably why it went through two idler wheels in 15 years. I fixed that problem. Went to the computer shop and bought 3 12v fans with a power supply. I installed one for each amp, and one for the tuner. I managed to install them on the back without altering it, other than some new studs and spacers to extend the back slightly. Runs cool if left on all day now!