RCA 7-HF-5 Consolette completed

[Hi-Fi-Mogul]

Hello all,
In between painful dental work, I've got
this 1956/7 RCA back together.

She sounds very nice with a 50C5 PP amp.

Much,much grime everywhere at the start,
but she's clean now.
I worked with the finish carefully, and
that's also as good as it will be.

The lid hinge's little locking ball bearing
was worn, and the hinge would not stay
locked.
I could not find any hinges I had
saved from other junked players.

When I took off the hinge, I thought it might
work if I reversed its position.
That did the trick, and now the lid will stay up.

I also have the tapered metal legs for her.
So, now to find her a good home.

[TC Chris]

I just looked up the schematic... 12AX7 and two 50C5s; selenium rectifier. Did you replace the rectifier? I had one die dramatically on me and never knew whether it was too old or whether the filter cap shorted. So the 12AX7 is a preamp and phase-flipper?

Chris Campbell

[William]

Nice job! I like the Maple finish. I want one of those in the 45 player.

Bill

[electra225]

Nice job! Did you install a stereo-compliant cartridge? I see you are spinning as stereo record.

[Hi-Fi-Mogul]

Hi guys,

1. Yes, installed a Pfanstiehl P-226 stereo jumpered
both channels to mono.

2. Re: Se rectifier, changed to 1N4007 diode.
12AX7 functions as you stated.

Thanks for your interest !

[back-2-mono]

Very nice. I have an SHF-9, the portable version of your player.
Next time you order parts from VM-AE, get an 865DS stylus for your P-226. The shorter cantilever will give you a bit more output than the 864 that came with your current cartridge. You'll get a bit more bass at lower volume due to the loudness taps on the volume control kicking in.

[Hi-Fi-Mogul]

I had to re-visit this RCA, as it developed an
intermittent loud hum.

After troubleshooting the obvious with no results,
I finally took the solder iron to re-flow some B- nodes and
the controls' wiring.
One node had a clog of wire strands that fell
off the terminal strip as I re-flowed the solder.

Finished off with applying both electronics and control
cleaner sprays to V,T,B controls.

Wow. Hum back to normal, and very enhanced
audo response. I forgot how good this little gal
was supposed to sound.

back-to-mono: I did place a Pfanstiehl 865 stylus
to replace the 864.
BIG difference in the P228 cart response.
Thanks for the advice.

[William]

Mr. Mogul. I have always wanted to hear one of the 7-HF-5's. They remind me of the console version that my parents had in their 1958 RCA Home Theater. Maybe someday I will get the chance to hear one like yours. Thanks for sharing.

Bill

[hermitcrab]

Looks good the blond finish was the big thing in the 50's , not sure how you replicate it ... is it just linseed oil or varnish on bare wood?

[electra225]

My understanding that it is a paint process. Not sure exactly what the process is. There is/was a guy on ARF who did a few blonde refinishes that looked great. I can't recall who that was.

[Firedome]

A lot of the original blonde pieces of the '50s were limed oak, where the wood was treated with caustic lime to lighten it then waxed or finished with clear lacquer. The process goes way back to Merrye Ye Olde England when caustic lime was used to prevent insect damage. In the '40s and '50s it became a popular look due to the move away from heavy looking dark and ornate furniture. It's become my favorite furniture style and finish, as clean-lined and light finish pieces look really good in smaller rooms like we have.

I also paneled the LR and DR in our summer place with T&G pine that I painted with water-thinned white latex paint then rubbed off while it was wet to create a limed oak blonde look that works well with all the natural pine trim and ceilings.
Cabot also makes a limed-oak stain that duplicates the look.

[Hi-Fi-Mogul]

Looks good the blond finish was the big thing in the 50's ,
not sure how you replicate it ... is it just linseed oil or varnish on bare wood?

This is not limed oak, but some kind of over cover
above a dark veneer.

I don't think this is a photo-finish, but I've no
experience to know for sure.

I noticed this as I was cleaning with 0000 steel wool
and Howards, and I had to be
cautious not to remove that "blonde" finish.

[William]

To me, the coloring looks like what RCA called their maple finish. It has the honey tone of maple which could be achieved on any wood.

Bill

[Firedome]

Agree, it doesn't look like true limed oak, not sure what the wood actually is but the color in the pic is closer to a light maple.

[electra225]

I won't name names for fear of being wrong, but awhile back, there was a thread on ARF where a member redid a blonde cabinet, I remember it to be an RCA much like this one. I have tried to find the thread with not much luck. It was maybe as long as ten years ago. Ebony and blonde use much the same techniques.

[Motorola minion]

Thanks for posting this thread, orthophonic RCA was popular for a reason, great sound!

The ceramic cartridges available: P-226 and P-228 are .5 and .8 volts respectively. This thread is teaching me something here that I may have also confirmed, but avoided asking V-M for advice every time I place an order for repair parts like this.

Please enlighten me, did the P-228 perform better in this case because this amplifier has one 12AX7 high-gain audio stage prior to the power amp 50C5? If so, it needed higher output voltage like almost all the "portable" and stand-alone record players.

I have used the Varco TN4 (Pfanstiehl P-226) or the EV-274 / BSR C-1 cartridge where it will fit, using Tetrad cartridges if the tone arm is too small.

RCA's often use three 6CG7 triodes prior to the 6V6 or 6BQ5 outputs. The Tetrad ceramic cartridge comes in three output voltages and them seems to be a tricky compromise between matching amplifier input impedance and cartridge output voltage.

[electra225]

RCA liked using the 6CG7/6FQ7 in their audio circuits. Magnavox used the 6EU7, but I suspect RCA used the 6CG7 due to the fact they put them in TV chassis and had them on hand. I don't know of any inherent problems or benefits using the 6CG7 over the 6EU7. The EU7 might have been a tad more "high tech", but I suspect not much better in terms of performance. A 50EH5 will put out a tad more power with a lower input voltage. This is why many of the "one tube wonder" record players used this tube vs. the 50C5. In my experience, the 50EH5 will sub for the 50C5 and may give benefits of greater output in certain applications. I believe your adaptation of a 12AX7 in place of a 6EU7 would work for the 6CG7 if you wanted to go that route. Zenith made the 6KT8 that was a pentode/triode, while the 6GH8A was a triode/pentode. I don't know why these tubes couldn't be used in audio applications in place of the 6EU7 and the 6CG7. This is not a scientific comment, just one gained from experience.

[Hi-Fi-Mogul]

Thanks for posting this thread, orthophonic RCA was popular for a reason, great sound!

The ceramic cartridges available: P-226 and P-228 are .5 and .8 volts respectively. This thread is teaching me something here that I may have also confirmed, but avoided asking V-M for advice every time I place an order for repair parts like this.

Please enlighten me, did the P-228 perform better in this case because this amplifier has one 12AX7 high-gain audio stage prior to the power amp 50C5? If so, it needed higher output voltage like almost all the "portable" and stand-alone record players.

HI Dave,
I think you are correct in saying that the P-228 did better
because of a bit higher output.
In many (if not most) of these little PP amp RCA's of the 1950's,
a Sonotone 2-T cartridge was used.
They are a great mono cart, and had a 1 volt (sometimes >),
output.

Ditto for the Astatic/EV "powerpoint" 81, 89 plug-in stylus/cart,
which put out 1.3 volts !

[Hi-Fi-Mogul]

And here is Ms. RCA with her cool legs !

[electra225]

Nice job, Mr. Mogul!

Is this one a keeper?