Pesky Philips Tuner Spindles

[Mikey405]

Hi all.

I've not posted much up here of late so I thought I'd put pen-to-paper (or fingers-to-keyboard) and write about my recent experience of a Philips multi-band tuner. This isn't intended to be a "how to" guide, more just a few observations I've made since repairing a number of these tuners. I'm in the middle of one such tuner fitted to a big Decca CTV so I'm trying to jot down notes as I go. This is in the way of a "Part 1" - All being well (and as soon as I can find a gash tuner to pinch a spindle from) then I will write up "Part 2", which will be how to put the thing back together again, which has its own problems.

The tuner in question is the kind used in various early Decca colour sets (CTV25, CS2510 etc.) along with some Bang and Olufsen sets and in various continental Philips sets. The button mechanism (or something very similar) was also used in the Philips PM5508 pattern generator.

The electronics in these tuners never seems to give too much trouble, the main issue being the mechanism - usually the grease on the button spindles has completely gummed up so that they are not even remotely twiddle-able. Often the latching mechanism has a similar complaint with gummy-grease and the whole thing feels generally nasty to the user.

If I can recommend before you go any further - Make sure you have a completely clear bench. There will be a lot of mechanical bits and bobs and they can be easily lost.

Before attempting to do anything to these mechanisms, it is advisable to remove the electronic parts from the selector assembly. The tuner itself and any microswitches can simply be unscrewed and set aside. The tuning indicator mechanism and its associated metalwork can also be removed easily and this should be put aside too. To remove the tuner, you may need also to loosen one of the "rack" pieces that slots into the pinion on the tuner drive. I tend to unscrew one of the rack screws and loosen the other so that I can "hinge" the rack out the way before removing the electronic tuner.

The latching mechanism should now be relatively easy to clean and lubricate without too much further dismantling - and if this is all that needs doing then you're a lucky person indeed. The spindles, on the other hand, are another story entirely. Not only do you need to strip virtually every single mechanical part out of the assembly but a lot of the mechanical components are quite delicate and will be liable to break when you attempt to remove them.

The black plastic knobs are one of these delicate parts; to remove them looks easy and involves applying a small amount of pressure to lift the edge of the plastic over a small white tab. Unfortunately this plastic will be well over 50 years old and unless the greatest care is taken then the plastic will break and there will be nothing to hold the knob onto its plastic "intermediate" spindle underneath.

Once each knob has been removed, a detent pin must be removed. This can be achieved by using a fairly hefty pair of pliers between one end of the pin and the end of the metal spindle. Carefully applied pressure will push the pin half way through the spindle, and then the end of a small bradawl (or similar) can be used to press the pin out through the other side.

If I can offer one piece of advice here - Don't be tempted to try and force the spindles to turn against their will by using pliers to turn the detent pin - you will snap the spindle off at the narrow section which holds the circlip. I know this through bitter experience - One of the buttons on the tuner I am working on has already had this done to it by, I assume, a previous repairer - so I'm a spindle down already.

Once the pin is removed, you must remove the various circlips and springs which tension the knob and the plastic band-selectors on each spindle. These are all fairly obvious and can be removed easily.

Next up are the two large metal "slide assemblies" - one each on the top and bottom of the selector mechanism. When the tuner pinion is in place, these slides move in opposite directions in a kind-of push-me-pull-you arrangement. These can be removed by unscrewing and pulling out the two long black metal "poles" which act as guides for the two slides. These tend to be rather gummy too, so put these aside for cleaning. Lift out the slide plates and put them into the "cleaning" pile too.

Next the guide at the bottom-end of the spindles must be moved out the way. This is held in by a single screw on each side. This guide can't easily be "removed" as such (unless you remove all the tiny circlips) but it can be pulled toward the back of the mechanism and gently manoeuvred out of the way without too much hassle.

Now the springs that tension the 6 band-selector slides can be unhooked and the slides themselves removed for cleaning.

With all the knobs, springs and circlips removed from the selector spindles and the spindle bottom-guide moved out of the way, you should be able to slide each spindle from its hole. Once each spindle has been removed, the 6 rubber buffers and small cup-washers should be removed and put safely aside.

Now you should have 6 steel spindles with a pair of aluminium-alloy adjusters on each rod. One thing to note is that these adjusters are supremely delicate and can be broken with hand-pressure so great care must be taken when releasing them.

Now for the fun part... Over the years, I've tried all manner of ways to release these adjusters. I've tried soaking the spindles in penetrating oil for weeks, I've tried soaking them in diesel and petrol and finally I came to the conclusion that soaking them is not the way to go. The only successful way I've found (or rather a pal of mine found) is to use heat. To this end I can recommend boiling the spindles. The way I do this is to get a plastic takeaway carton, put the spindles inside and cover them with Plus Gas penetrating oil. Making sure that no two spindles are touching, I then put them in the microwave over, cover them with a glass bowl and give them 60 seconds. The reason the spindles shouldn't touch each other is that you don't want to form a closed-loop which will cause sparking. I am quite sure this is supremely dangerous and possibly water in a saucepan on the stove may work just as well but, as I said earlier, this isn't a how-to guide - just notes on how I do it.

The spindles should now be nice and hot so be very careful as you remove each one. Using your hefty pair of pliers with LOTS of kitchen-roll in the jaws, grip one end of the spindle tightly and, using your hands only (or gloves if you like - don't forget it will be very hot), gently rock each adjuster back and forth until it starts to move. Don't use too much pressure because, as I noted earlier, they are very delicate and will break very easily. If they will not move then they may need to be heated longer. Don't forget that each spindle has two threads - one in opposition to the other: As one adjuster moves towards you, the other will move away.

Once each adjuster starts to move, treat the spindle to some penetrating oil (or, if you're using the extremely dangerous Mike-Bennett-patent-boiling-oil-method outlined above, dip the spindle back into the oil) and carry on gently loosening the adjustor until it runs free the entire length of its thread.

And there we have it. "End of Part 1" as they used to say on TV. My Decca tuner now just needs to be put back together - as soon as I can find a spare spindle and knob from a gash tuner. (I suppose that's a cheeky way of asking whether anyone has one.)

Thanks everyone.

Kind regards.

From Mike.

[Heatercathodeshort]

That looks a very neat job Mike. 'I told yer not to take it apart if yer couldn't bung it back together again..' Regards, John.

[Mike Phelan]

An amazing job and a superb write-up, Mike.

[Welsh Anorak]

I suppose Part Two is titled 'How to repair an exploding microwave oven'?
I'm surprised you didn't title it Hey Presto(matic)...
Seriously, I think I know where there's a B&O mono chassis with its tuner - the owner wanted a nice cocktail cabinet - ouch! The innards are supposed to be coming my way so if you're lucky there might be a tuner there, though I'm not 100% sure it's one of these.

[Mikey405]

Hi John, Mike and Glyn.

Thank you for your kind replies.

'I told yer not to take it apart if yer couldn't bung it back together again..'

That may well be quite prophetic John.

An amazing job and a superb write-up, Mike.

I'm not sure I'd go quite that far Mike but thank you anyway. You may want to retract your statement once I've thrown the whole lot in the bin in disgust...

I'm surprised you didn't title it Hey Presto(matic)...

Oh dear. I think I probably would have used that title Glyn - if I'd had the wit to think of it.

I think I know where there's a B&O mono chassis with its tuner...

Oooh. I shall cross my fingers then but carry on the search just in case it isn't the same kind. I'm sure I've saved a small bag of these spindles and knobs etc. but I can't find them anywhere.

Thanks all.

Kind regards.

From Mike.

[Tazman1966]

Excellent job Mike. I saw first hand how you had the patience and skill to free up the tuner in my Korting Transmare with a similar problem an some of the spindles although in my case we didn't need the boiling method as they weren't completely seized - only nearly.

[Mikey405]

Thanks Tas. Patience - possibly. Skill - definitely not. It's just taking things to bits after all and anyone can do that.

I can't remember whether your Korting had a similar Philips tuner or a Telefunken or something like that. I guess gummy-grease is gummy-grease though, whatever the brand.

Thanks Tas.

Kind regards.

From Mike.

[Welsh Anorak]

No, Mikey, it's putting things back together where your skill shows.
I've been given the B&O and sadly it has a varicap tuner. Sorry!

[Mikey405]

Not to worry re the B&O Glyn. Thank you for the kind thought anyway. I've temporarily cheated anyway and used the mechanics from another tuner (kindly provided by our own Mr Boynes) whilst another spindle and knob are located.

Thanks again though Glyn.

Kind regards.

From Mike.

[ctc15]

Hi all
Since the problem seems to be dried out / oxidzed hard grease would car brake / carburettor cleaner work?
I have a B&O and a Decca CTV19 with this problem.
Keith

[Mikey405]

Hi Keith.

I did try carb cleaner but even with a hefty soaking it didn't make much difference. I even kept the spindles in thinners for a couple of weeks and no difference.

I was talking to a pal of mine in France yesterday evening and he said that heating then with a hefty soldering iron has worked for him. Another pal of mine used a tiny blow torch which did work okay but melted the springs.

Once the tuner is out though Keith, it's not quite as daunting as it looks to remove the spindles. I think you just have to be very careful, work methodically and take lots of photos as you go along.

Thanks Keith.

Kind regards.

From Mike in Lockdown-Solihull.