Going through my pile of round-to-it machines, I discovered this little beauty.
It's a JET 606.
Of the many classic late 50's tabletop sets, this is, in my opinion, one of the most beautiful models and
a set like this should be used and enjoyed, not just sit around in a large carton in a storage facility as
it has been doing for the last 15-20 years.

Martin

A beautiful model and a wonderful chassis to work on.
I recently restored a JET 606 Moderne, which is exactly the same chassis, only in a more stylish
and modern, more boxy cabinet.

Unfortunately, that one didn't make it to the new owner in one piece but that's a completely different story.

Martin

Looking at the JET 606, it seems to be nice and intact.
The dial lettering shows a little blurring. Unfortunately, this is quite common for some models but in this
case it is not very drastic.

Martin

Very nice Martin.

I have a couple old radio sets myself I am planning on reworking this summeer. Not B&O but USA brands from back in the days when we actually made stuff like that.

Beautiful, just beautiful. Is this another restoration thread?

Yes, I think it will be another resto-thread.
It has been some time since my previous one and this set seems to be a good candidate.

The cabinet is largely undamaged, it has the tiny ding and the odd scuff here and there, nothing drastic here either.
The rear and underside covers are in place and looking their best.

Martin

All knobs are present, and most of them seems to operate nicely.
Actually only the dial knob does nothing. It won't rotate, but just sits there like it was glued to the chassis.
This will have to be investigated. My guess is that the dial string has snapped and is now blocking
the mech somehow. Still, I would imagine that a fault like that would still allow for a little movement
of the knob, if nothing more than just a spring tension feel. I will have to look into it when I get the covers off.
And exactly that will be the next thing.
Off with the back and let's have a look inside.
All valves are present and in their correct positions, it seems.
Dust in a nice layer.
A little amount of spiderweb.
A little surface oxidation to the aluminum cans.
Nothing uncommon and nothing alarming.

Martin

The JET 606 was made for the 1960 season and was featured in the 1959/60 catalogues, actually
the Moderne version took pride of place on the page.

Martin

The model name JET suggests a position right in the middle of the model range, functionality-wise.
Jet was a bigger and better build than a MINI but cheaper and not quite as
technically advanced as a GRAND PRIX.

Martin

That brochure is gorgeous.

The JET 606 is a fairly large set that typically saw use as the daily set in the livingroom of a middle-class home.
It has provisions for connecting a record player and an external speaker.
Being a Bang & Olufsen set of this nature, it will be a good performer and thanks to
the PL84 output valve, it will provide a whopping 4,5 Watts output power.
That was quite an amount at the time and no doubt it will easily be able to fill a normal livingroom with sound,
especially if an additional external speaker is connected.
Other features are the built-in FM antenna and an also built-in and even rotatable AM antenna.

Martin

tone control, a magic eye and a two-way speaker system

Martin

The plug-in module that sits right in front of the output stage with its ECC83 preamplifier valve works
with the record player input and functions as an adapter for different types of pickup cartridges.
The one currently fitted is for a Crystal type (high ohmic) cartridge.
Glued to the inside of the cabinet is an envelope that originally held the schematics.

Martin

Hey, the sheet with the schematics is still in there !
I will leave it there. I will work from the service manual anyways and the schematics may
come in handy in 50 years when the next repairer will be servicing it.

Martin

Actually, that schematic is practically all you need if you have a little basic experience with servicing
valve sets. I am particularly fond of the valve pinout drawings at the bottom of the page.
Expected voltage readings are printed here for selected valve pins which allows for a fairly quick
diagnose of the most common faults. Very nice.
You won't find anything like it in any modern set.

Martin

Bottom cover

Martin

Off with it

Martin

More spiderwebs

Martin

But nothing the vacuum cleaner can't handle.
There, much better.
Now I can see the components.

Martin

Actually, I can now also see why the tuning knob has seized.
The dial string looks fine but the knob spindle that also bears the large flywheel has an amount
of surface rust, just enough to have rusted solid in its bearings.
The bearings are square pieces of fiberboard with holes.
A single drop of oil in each bearing and a little exercise saw
the tuning pointer travelling nicely again when the knob is rotated.
One fault cured.

Martin

Well, back to taking out the chassis.
It's held in place by two screws.
One came out right away, the other one had about half an hours work worth of rust.
I had to oil the threading a bit to losen it but out it came.

The two speaker leads had to be cut and the chassis will now slide out.

Martin

It comes out in one piece, bringing with it the dial and all knobs.
Wonderfully easy to work with now.

Martin

A typical build from B&O at that time. Using both the old fashion birds nest structure and
printed circuitboards.
In this set, the FM frontend is housed in a shielding metal casing and is built on a circuit board,
the amplifier is on another board and the rest is a birds nest construction.

Martin

The chassis is on the bench now.
Visual fault finding in progress.
There are no very nasty surprises but still a couple of issues stand out:
The fuse and its holder has oxidized to a point where replacement is the only way.
It seems to be almost a rule in these old sets and luckily it's an easy fix with two new clamps and
a new fuse.

Before

After

Martin

There are more things that need to be checked before applying power.
The suppression capacitor is normally one of them but this set does not have
a suppression capacitor but instead a kind of decoupling capacitor that sits across the rectifier.
That is the blue capacitor to the left.
This little sorry looking thing was placed right next to a couple of warm ceramic power resistors. No wonder
it grew tired. It's a 5Kv component and in its current state nothing I would like to put across anything mains
with me nearby.

A brand new MKP type foil capacitor replaced it.
A couple of pieces of heat-resistent silicone wire insulation was mounted to its pins for added protection.

Martin