Pilot U650

[Devon60Ben]

Never heard of Fahnestock connectors Mike but they do look simple and effective. Banana plugs are a bit modern looking but they will be out of sight at least

[Cobaltblue]

I suppose I should more correctly describe them as Clips rather than connectors (I struggle to grasp names of things these days!)

Not sure what the perceived advantage was except I guess very cheap.

I am sure the salesmen could come up with a dozen advantages

Cheers

Mike T

[Gabe001]

Looking at some pictures online I think mine has been modified slightly and I've got the earth and aerial connection sockets above in the top right corner (4mm sockets). So I think it's the clips for you as the others have advised. See picture.

If you look up my thread about the same model I've asked pretty much the same questions you are asking (it was also my first set) and they were answered in quite a bit of detail.

Can I ask if yours has a faint mechanical hum when it's on? Mine does and I'm not sure whether it's to be expected from this set or not.

Gabriel

[Devon60Ben]

Thanks Gabe - very useful - I will look up your thread.
I have not yet fired the beast up, wanted to get the new caps installed (which have just arrived with a bag full of resistors!!) first in case something was shorting and took out a transformer or something.
I am expecting some interference on my radio reception if I can get it working as i have no idea about wire routing / dressing etc and probably have the wrong spec wire here and there but not expecting a mechanical hum..Is that with the Radio and Pick Up Jack?
Were your HT Smoothing and other caps all replaced?
I couldn't see your sockets at first but did in the end right up under the lip of the top cross-brace. I hadn't thought of mounting there but that's a much better place. Except that the flying leads may need to be routed away from something to avoid any induced Hum or interference if this is possible?
I was thinking about a bracket to position them flush with a new back panel that was cut around the bracket to reveal them. If no issue with the wire routing - will await feedback from the guys on here - will steal your idea and mount the sockets up there!

[Devon60Ben]

The Tuning Dial has now been reassembled - I think I read somewhere that it was an Aeroplane Propeller type? or something which is exactly how it looks.
The dial plate? or whatover its called with the writing on is plastic and although now cleaned has a few brown spots of staining which will not come off so i will have to live with them.
The thing tracks well with exactly 180 degrees of pointer movement and it looks like as you select different frequency bands and tune then the lamps for the right quadrants will illuminate only so that should be cool.

[Gabe001]

Indeed the dial lights up in quadrants and it looks quite impressive. Day and night pics below. The magic eye lights up too, although I was told that mine is quite dim.

Light yours up when ready and let me know if you get a faint mechanical hum (not speaker hum) when you do. It's inaudible when the radio is playing.

[Devon60Ben]

Decided to remove the speaker so I could access the Magic Eye as it's the only Way to do that. There is a raised wooden spacer housing that the speaker mounts on so that the tube is spaced away from the aperture correctly. A whole load of trouble just to get the look they wanted, but hey ho. The bean counters these days would have convinced them to move it - or not have one at all!
Anyway it looks like the original 65G tube made by Kenrad made in USA so not expecting it to be bright. The Russian tubes available look a slightly different colour or just brighter but both look good to me. Will see how it looks when fired up.

[Devon60Ben]

Got a bit carried away installing new caps and resistors - All Components associated with V1, V2 & V3 Done plus Magic Eye Plug Socket.
Installed a temporary power cord salvaged off an old hoover and an in line fuse holder between on/off switch and power transformer as there was no fuse at all.
Just V4 & V5 to go now - marking off the schematic as I go.
Wondering about voltage measurement now. The 582 sheet refers to voltage measurements being taken using the 1200V scale of a universal AVO meter. I believe this will measure differently to my DMM. I have a heathkit VTVM too. Not sure about Ohm's per volt or impedences yet - will do some research.

[Sideband]

Originally Posted by Gabe001

Can I ask if yours has a faint mechanical hum when it's on? Mine does and I'm not sure whether it's to be expected from this set or not.

Don't know this set personally but in general terms a 'mechanical hum' can be caused by the mains transformer humming slightly (loose laminations) which can cause a 'buzzy hum'. Harmless nothing to worry about …..if it's a bit loud you may be able to reduce it by tightening the transformer clamps if possible.

Another form of hum is the induced type. It's caused by the AC field of the mains transformer being induced directly into the output transformer...usually due to positioning of the transformers.....one should be at 90 degrees to the other or sufficiently separated or even screened....in some sets the output transformer is mounted under the chassis. The induced hum very obviously comes from the loudspeaker at the moment of switch-on but may reduce slightly or change as the valves warm up. Some sets are more prone than others.

[turretslug]

Originally Posted by Devon60Ben

Decided to remove the speaker so I could access the Magic Eye as it's the only Way to do that. There is a raised wooden spacer housing that the speaker mounts on so that the tube is spaced away from the aperture correctly. A whole load of trouble just to get the look they wanted, but hey ho. The bean counters these days would have convinced them to move it - or not have one at all!

I'd wondered how they accommodated magic eye and speaker together like that, could they have used an annular magnet with the eye socket in the centre of the speaker frame, reminiscent of those Bf109s with a cannon firing through the hollow propellor hub and nestled in the vee of the engine. The magnetic field might have detracted from the eye action, though. The acoustic purists probably worry about the loudspeaker working down a tunnel, even a short one, but it was an effective way of highlighting the presence of the eye, I think it was one of the first sets to accommodate what must be one of the nicest accessories of the thermionic era.

Unfortunately, the working life of magic eyes is notoriously short, it's a bonus that one of that vintage gives any glow. On my Marconi 559 (also pre-war, Y61 magic eye) I made up a small steel bracket at the back of the chassis with a heater on/off toggle for the eye, so that it can display for show but otherwise stays off.

[Devon60Ben]

Originally Posted by turretslug

I think it was one of the first sets to accommodate what must be one of the nicest accessories of the thermionic era.

Unfortunately, the working life of magic eyes is notoriously short, it's a bonus that one of that vintage gives any glow. On my Marconi 559 (also pre-war, Y61 magic eye) I made up a small steel bracket at the back of the chassis with a heater on/off toggle for the eye, so that it can display for show but otherwise stays off.

Agreed - I love the magic eye which was what attracted me to the set in the first place. I was thinking about eye brightness saving and your switched heater is an excellent idea - i may "borrow" that one

[Gabe001]

Originally Posted by Sideband

Don't know this set personally but in general terms a 'mechanical hum' can be caused by the mains transformer humming slightly (loose laminations) which can cause a 'buzzy hum'. Harmless nothing to worry about …..if it's a bit loud you may be able to reduce it by tightening the transformer clamps if possible.

Another form of hum is the induced type. It's caused by the AC field of the mains transformer being induced directly into the output transformer...usually due to positioning of the transformers.....one should be at 90 degrees to the other or sufficiently separated or even screened....in some sets the output transformer is mounted under the chassis. The induced hum very obviously comes from the loudspeaker at the moment of switch-on but may reduce slightly or change as the valves warm up. Some sets are more prone than others.

Thank you very much. Not a problem at the moment, but will keep an eye (ear) on it

[Devon60Ben]

Originally Posted by Devon60Ben

Got a bit carried away installing new caps and resistors - All Components associated with V1, V2 & V3 Done plus Magic Eye Plug Socket.
Installed a temporary power cord salvaged off an old hoover and an in line fuse holder between on/off switch and power transformer as there was no fuse at all.
Just V4 & V5 to go now - marking off the schematic as I go.
Wondering about voltage measurement now. The 582 sheet refers to voltage measurements being taken using the 1200V scale of a universal AVO meter. I believe this will measure differently to my DMM. I have a heathkit VTVM too. Not sure about Ohm's per volt or impedences yet - will do some research.

A before and after for the V1 / V2 End. Hopefully will get the rest completed by the weekend.

[Hartley118]

Originally Posted by Cobaltblue

It was quite common on American sets (and late 30's Cossor sets ) to connect Aerial and Earth via a flying lead with a Fahnestock connector

I have a very similar Pilot set, though without the nice magic eye and with the later octal valves. And yes, it has those flying leads for aerial and earth just hanging out of the back instead of proper wander sockets. Those flying leads initially gave me the impression of a cheapo American design, but it’s actually a very good performer - and the illuminated ‘aeroplane’ dial is a delight!

I have a few other sets of American origin, but I’ve never come across another with those cheapo flying lead connections. Maybe they were a quirk of the Pilot design.

Martin

[1100 man]

Now, I don't usually go weak at the knees when I see radios, but that picture in post 26 is gorgeous!! There is just something about American styling from that period that I find delightful.

If the Victorians built radios, I can just imagine they would have looked like that! Very fancy with lots of intricate detail.

Out of interest, I assume it was built by Pilot in the UK, and is not actually an American set?

All the best
Nick

[turretslug]

Not just a pretty face, either, with its tuned RF stage and triple-tuned IFTs. A fine example of the art.

[Devon60Ben]

Originally Posted by 1100 man

Out of interest, I assume it was built by Pilot in the UK, and is not actually an American set?

Found this on a small plate inside my one Nick.
It may be too small to read on the photo but says:
This instrument is manufactured under licence granted by Electric & Musical Industries Limited (EMI), Hazelpat Limited, Marconi's Wireless Telegraph Company Limited and Standard Telegraph & Cables Limited etc,
But no mention of where it was made.

[Hartley118]

It was probably made at the Pilot factory in Park Royal, London to a largely American design (with the addition of a long wave band).

The UK manufacture would be under licence in respect of relevant UK patents, but interestingly only for domestic use and not commercial. The Hazelpat reference is interesting, presumably reflecting its American design origin, a patent pool owned by Hazeltine, Philco and Majestic.

Martin

[Devon60Ben]

All components have now been installed and checked twice. I now need a short break to think about the steps to check prior to firing it up for the first time and to get organised - so far this is part of the plan:
The speaker and magic eye will be connected and a 1 meter length of wire connected to the antenna.
Currently a 1A fuse has been inserted.
The dim bulb will be on with the variac / isolation transformer used to energise slowly which I will look at on the DMM.
Fingers will be crossed but hovering over the off switch!

[Devon60Ben]

Ok so the first test has gone as well as can be expected. There has been no smoke, explosions or other issues. The set is now off the limiter and at 240V input. I am listening to a scratchy Radio 4 which has never sounded so fascinating before!

There is no glow at all from the magic eye which was not really surprising although the heaters are glowing.

The dial lamps all work depending on the band selected.

There are 4 positions of the band selector switch and currently fully counter clockwise which I think is long wave as that's the segment lit up with the needle pointing to 1540 meters - now some sort of gardening programme.

The second position of the selector and all lamps light up but no sound at all. I think this should be the top half of the outer circle illuminating which is medium wave. So there must be a connection issue here.

The third position selects the bottom half of the inner circle to illuminate but cant find any channels at all just static, the dial indicates Short Wave.
The last position illuminated the bottom half of the outer circle but again only static.

Need to try the Pick Up input next.