Interesting, seen two turntables recently, both belt drive. The belt on one had broken and was jelly. The other had had the monkey who had been fiddling with the adjustment screws. The latter was a transcription type. Unlike the old BSR & similar both were just mounted on a Morse Taper. As soon as it is turned upside down, the platter falls off.

In the latter I bet that was to fiddle with the speed adjustment; Then there was no idea on how to put the belt back on.

Where there are moving parts & Collaro was jammed. A lot should be serviced every 500 hrs and it never happens. The older grease soaps dried out & blocked & glued parts.

These will never work properly until you get rid of every trace of it and using new grease mixed with the old is also risking it going solid. Corrosion is your enemy as well. I believe Philips often used Shell Alvania II. I use Inox MX6 (food grade) which comes in a convenient tube. there are varieties of it. Read the specs. Industrial supplier.

Do watch the old cartridge's. I have a Philips set here looking for a home & it is magnetic & electrically floating, needs DC blocking caps, & to top t off its Back biased.

Document uploaded.

Interesting reading. The record player has the arm which finds out the size of the record, like mine did.

You put the record on the spindle top part, hold it in position with the fat lever. Start up the record player, the little arm swings across to get the diameter, then the record drops onto the platter, then the tone arm moves to the proper place, and the music (or whatever) starts.

The speakers look good enough to work with, I wouldn't worry about a couple of small holes.

Very repairable, the only problem is how you're going to mount the radio, speakers, and player once they work.

Looking forward to how this pans out.

I have been well enough to do sit down work, so got the chassis to a working state.
There were a few parts that needed changing as described.
I investigated the output tranny as the speaker load appeared to be less than 2 ohm and found that was correct.
I also got the changer running with little problem and grafted in a Chinese Jaycar cartridge.
All of that in part 2 which I will send to Brad to post in send 1.

Fred.

Part 2 uploaded.

In my experience, black 6BV7s are the more common variety, so they are probably ok. Just like you may come across a black 6AQ5.

The only thing really is to make sure the 6BV7s don't get too hot or they can warp and short internally. Using common sense with the grid bias will keep things under control.

I'm sure I've seen this kind of phase arrangement discussed in an article somewhere, but I cannot recall where. I wonder if you pull out the lower 6BV7 will sound still come out.

Looks like that record player will be fine for some years.

I have noted, where tubes get seriously hot: Stoves with the miniature CPU cooling fans being used on them. Pushing air from the bottom.

I came across the same 'modification' in a Messa Boogie valve amp. A CPU fan driven by a off-rigger board with a rectifier and electro hooked up to the heater supply.

The 6BV7 was a valve that never lived up to its marketing promise to make a cheaper 4 valve mantle radio that performed as well as a 5 valve model.

In service, in my experience, they lost their mojo very early in life. A newer replacement I fitted into a repair for a friend was in a taller envelope and it seemed to work much better.

The design of that radio, an AWA, had considerable complexity around the AGC and biassing of the 6AU6 (a sharp cut-off pentode) to get enough level at the detector to create an acceptable performance as the volume was turned up.

Notably, when AWA designed the cut-down 211 / 212 TV chassis in 1957, they used a 6BV7 and a single stage of sound IF. To get adequate sound volume, the level from the ratio detector had to be increased. So the sound IF could no longer function as a limiter, transferring all the AM rejection responsibility to the ratio detector. When TV broadcast sound carrier levels were reduced, the sound in this model became quite marginal.

AWV were the only company to make the 6BV7 which is why they are so hard to find today. Very few other manufacturers designed them in. Healing were a big AWV client so it's probable they had this design presented to them because AWV were anxious to move some 6BV7s.

I have finally finished this project and can happily stow it into the collection.
The previous owner had a look at it and simply stood amazed.
I gave her the first option on getting it back from my estate if I cark it first, (no cost).
It has taken well over a year to sort it with breaks for bad health, fatigue and other projects.
As usual I'm just sick of it and want to get on with the next project, while I can.

That will be a guitar amp to match my lightweight bass and be a Fender Bassman copy.
That by the way was not a very good amp despite all sorts of glowing testimony.
I made Bass amps that would eat one of those and fill a small club or auditorium with thumping bass.
When one of those Fender or Peavy things was used we would have to mike the thing and feed it on to a 200 watt stack to be heard!

However I am under orders to make a light weight gutless distorted 60 watt amp so be it.

Check out the latest SC issue for an article about why the Bassman was so good.
(Not in a large club or on stage in front of of 1000 screaming girls it wasn't!)

Cheers, Fred.

Part 3 the healing project sent to Brad.

Some of the most interesting amps I have seen for domestic use have tubes never designed for that. We used a HMV R series with a #807 as a single ended output as a demonstrator for the radio club and that had no real issue filling the cattle pavilion it was in with noise.

I have never really looked at the PA line amps for sound quality, albeit there is one here with two 6CM5 switchers running 300V class B and an an abandoned one that takes six of them.

Interesting Marc.
The 6CM5 was used by AWA in P.A. amplifiers and I suspect they used 6CM5's made by AWV that worked alright in a linear mode.
Not all brands of 6CM5 worked as amplifiers being basically a switchmode valve for TV sweep duty.
I tried to use 6CM5 but found they did not react very well tending to be very unstable and clip sharply.
Once I woke up and used 6DQ6 or EL34's all those problems went away.

The EL34 (6CA7) was a honey of a valve. I ran them with 700 volt on the plate and 350 volt on the screen and could measure 90 watt per tube pair easily. Pity about the single end construction with the plate pin on the octal base.
I had flash overs and had to take care with socketing and use ceramic sockets in some builds.

Of course as soon as transistors came in I could easily get 90 watts with four 2N3055 or 2N34442 at 1/10 the DC voltage.
I never went for the high voltage transistors running on 140 volt like some builders, I preferred to make an amp at 70 volt and never see it again.

Nowadays you can buy an amp with 500-watt output that sits in the palm of your hand all switchmode running in class ZZ or something and the things we made are just boat anchors.

Fred.

Fred: Its amazing how things have changed. A car club I am a member of, had a member turn up with a Jaycar Amp last month. Cordless microphones integrated and quoted as 300W RMS.

Part 3 uploaded to the original post.

Looks like I have come to the finish of this project.

I removed the 6BV7's and replaced them with 6DX8 triode pentodes.
The output transformer matches an 8 ohm load nicely.

The main reason for working on the set again was the farmyard of crackles, pops, whistles making it useless.
It is now a nice sounding quiet unit, I have written a part 4 and will send that to Brad to add to this string.

Fred.