It's got tubes in it so... RCA ivf-246 console

[loudnoises]

Have a chance to pick up a really nice looking mcm style console from a buddy. Been sitting with his parents for decades, and it's mom level clean.

And oddly, it's an RCA. Model ivf-246. 1961/62 best i can tell, tube and seemingly stereo? Found what seems to be the service manual, so it's possible.

Very tempted, but to be frank, I don't need another boat anchor. Anyone have any experience with anything from RCA of the era?

Of course I could always just strip it and put in modern electronics...

 

[Mwdan]

I just looked up the model on youtube and I'd say it's a very worthwhile candidate for restoring. I really like the style. Definitely tubes and shouldn't be hard to work on with some guidance.

 

[Tinkerbelle]

According to Radiomuseum that console has the RS-193 tube amp, which uses single-ended EL84/6BQ5 tubes. So should be relatively simple to work on for any restoration. Audio-wise, it should be sweet sounding though low power.

Recent thread on that amp: Rectifier for this RCA EL84 amp console pull?

 

[Dswankey]

.. I don't need another boat anchor.

Not even close to being a boat anchor, RCA console pull amps are pretty sweet

To add to what Tinkerbell mentioned

RS-193

3-VF-065 'Baritone' Ch= RS-193E R-Player RCA RCA Victor Co. |Radiomuseum.org

3-VF-065 'Baritone' Ch= RS-193E R-Player RCA RCA Victor Co. Inc.; New York NY, build 1962 ?, 2 pictures, 5 schematics, 4 tubes, United States of America

www.radiomuseum.org

Modded

Tube Amp on a Plank # 1: RCA Victor RS-193 Single Ended Stereo Hi-Fi Amplifier

Jim Clifford, Jimmy Clifford, guitar, tube amp, blog, James Aoyama, bicycle,

origaminightlamp.blogspot.com

Anyone have any experience with anything from RCA of the era?

I have a modified RS-177A and it's sweet

 

[loudnoises]

Well i think that's good enough for me, I'll get it next time they are up there.

Just gotta figure out where to put it. And decide which turntable to put in there. And figure out what to do with the imperial...

 

[Lavane]

Not even close to being a boat anchor, RCA console pull amps are pretty sweet

To add to what Tinkerbell mentioned

RS-193

3-VF-065 'Baritone' Ch= RS-193E R-Player RCA RCA Victor Co. |Radiomuseum.org

3-VF-065 'Baritone' Ch= RS-193E R-Player RCA RCA Victor Co. Inc.; New York NY, build 1962 ?, 2 pictures, 5 schematics, 4 tubes, United States of America

www.radiomuseum.org

Modded

Tube Amp on a Plank # 1: RCA Victor RS-193 Single Ended Stereo Hi-Fi Amplifier

Jim Clifford, Jimmy Clifford, guitar, tube amp, blog, James Aoyama, bicycle,

origaminightlamp.blogspot.com

I have a modified RS-177A and it's sweet

View attachment 3690917

Those look like some pretty decent OPT's for a 6BQ5 PP console amp.

 

[loudnoises]

Those look like some pretty decent OPT's for a 6BQ5 PP console amp.

"Instead of two single-ended output transformers, each 6BQ5/EL84 is connected to the primaries of its own double-ended output transformer. The B+ voltage from the power supply is hooked up to the center tap, one primary leg is connected directly to the 6BQ5 plate, and the other leg, which acts as an additional filter choke, goes to the screen grid of each 6BQ5, through a dropping resistor (and also provides voltage to the plates of the 6EU7 driver tubes). This ingenious use of two double-primary output transformers, with their added AC ripple filtering, helps to keep the amplifier's noise floor down - a good thing in general, especially since single ended tube amps tend to have a bit more inherent noise than push-pull circuits."

I understand about 90% of this. But this makes it rather uncommon?

I have a pair of 30a, and seemingly a few other 6bq5 amps, so I'm in somewhat familiar territory. Somewhat.

 

[gadget73]

Its a hum-bucker config, basically its a cheater way of getting extra filtering without having to install a choke. Looks like this




The screen end of things gets some extra filtering, between that and the 3.9k resistor and 35uF to ground its reasonably well filtered.

 

[Mike Stehr]

Along with 80uF right off the 5Y3 for B+.

I had a couple of theses amplifiers. One from a stereo console, and another from a television/stereo console.

 

[gadget73]

Sure, but the screens also get the benefit of the resistance and the choke effect in the transformer, so does the 6eu7 stage. It likely also injects a bit of hum out of phase which helps with what the plate gets.

Its not a lot of filtering, just 2 stages. Very much an economy move but if done correctly it works.

 

[atmasphere]

The big downside to the RS193, like the other RCA pulls, is the OPTs are designed for one speaker impedance only. The RS193 being set for 4 Ohms. If you run higher impedances its OK, just doesn't make full power.

They are not great in the bass region, so benefits from careful use of the bass control and nice efficient speakers. I'm sure the ones in the cabinet are very easy to drive.

After rebuilding the electronics in a Grundig a few years back, it sort of made me wonder how things might turn out of you put more high end drivers of similar efficiency in the cabinet...

 

[loudnoises]

For the moment the intent is to keep it as a unit, so we'll see what it sounds like. No big drivers like the imperial, but a nice small footprint. Drivers aren't big so I should have plenty of options.

 

[AlexHempel]

That output transformer scheme is very cool and a good incentive to leave the original OPTs (for better or worse). Wouldn't really be the same amp without them.

 

[loudnoises]

That output transformer scheme is very cool and a good incentive to leave the original OPTs (for better or worse). Wouldn't really be the same amp without them.

Have no fear, it's not my style to break stuff up. There's plenty of parts out there if I want to build something funky. Plus, this is my buddy's parents. They just had to move into assisted living and he's dealing with all that and unloading the house. Thankfully they didn't have much crap, but he's not really keeping anything and I'd like to give him the option of getting it back one day. I have become the caretaker of all the old audio of my crew (big shock there) and it's a pattern I've seen.

I'm a bit intimidated by redoing the tuner, I can replace parts but then making it tune correctly is all voodoo.

 

[gadget73]

Fair bet you won't have to do anything with the tuner outside of the usual paper and electrolytic caps. Those won't affect alignment. The stuff that does rarely goes bad anyway.

 

[dietz31684]

Good on you for being the caretaker of gear. I wish I had kept my dad's advents and CDs. When trying to empty a house in a few weekends you act on necessity. Id love to gave his old speakers back...but they're in the dump.

 

[loudnoises]

Good on you for being the caretaker of gear. I wish I had kept my dad's advents and CDs. When trying to empty a house in a few weekends you act on necessity. Id love to gave his old speakers back...but they're in the dump.

My father still has his records, I have the sl72, sx-990, and xr-7b speakers that went to nam with his buddy and he purchased before I was born. So I can still listen to the same system he had when I was born. The table needs cleaning, the sx-990 needs new pads, but the fishers are in my bedroom system.

 

[atmasphere]

I'm a bit intimidated by redoing the tuner, I can replace parts but then making it tune correctly is all voodoo.

Tuners really are not that hard. Helps to have a schematic and some test equipment, in particular a Digital VoltMeter (DVM) and an oscilloscope.
The first thing to do is find out if it plays anything. From there we can sort out what it might need.
Typical problems are the filter caps, which are usually very small values, often fail. If they go bad the radio will have very weak reception. It won't work well if the tubes are weak too, so they likely should be tested first.

They also go out of alignment. Dynaco published in their FM-3 assembly manual a simple way to align the IF (Intermediate Frequency) transformers and front end. The only really tricky bits are the ratio detector and aligning the multiplex system (if it has one).

The AM section is easier. If you can get something out of it, aligning that can be done with nothing more than the right alignment tool and a functional amp and speaker.

 

[init4fun]

Fair bet you won't have to do anything with the tuner outside of the usual paper and electrolytic caps. Those won't affect alignment. The stuff that does rarely goes bad anyway.

This, this, a million times this. Do not tweak any IF can adjustments till you've replaced the likely bad capacitors and the possibly bad resistors. If after replacing the bad caps and resistors you have reception difficulties, troubleshooting by checking circuit voltages would be the logical next step.