Bush VHF61

[yestertech]

having seen quite a few of these sets now, there are definitely two classes of '61 - Those which should be tackled and those which should be left well alone !
The bad sets are inherently "deaf" - no amount of cap changing and alignment will get them to perform. They share this trait with specimens of their bigger brothers the VHF64. Fortunately, the spares come in handy.......

This one was in a job lot of radios looking very grubby and sorry for itself. But I like these little beauties. Thanks to the extra IF stage they are great performers when given the TLC they deserve. They are also very frugal on shelf space !
Under closer inspection, this one was mainy just grimey. After an initial power up to confirm it wasn't a cadavre, the HT pSU was applied via the trusted 15W lamp to the smoothing caps, until the leakage looked satisfactory.
Meanwhile, the cabinet was T-cutted, then polished with a little dark tan, which looked great.
The gold painted areas ( fortunately not rubbed near the buttons ) got a good going over with Greygate plastic polish, which was also use on the brasswork. The knob outer trims had done their usual 'expand-o-matic', so the inserts were gently cut and the excess removed before supergluing back. They were then popped into the drill chuck via an old "addashaft" spindle and given a good spin on a polish cloth.
The dial was removed and the painted area behind given a quick swish with foaming cleanser, plus a new dial bulb. The dial glass had the foaming cleanser treatment followed by isoprop alcohol, which leaves it glistening like the day it was made !
All of this "cleanliness" made me want to see if the set was going to be up to the mark performance wise. After changing 'that capacitor' ( amazingly only 1v leaking ! ) the set gave a good account of itself on AM and FM.
One snag, the volume control was either off or full on - no amount of switch cleaner helped. Being a dual concentric job made it seem like a no hoper. I then remembered that the last '61 I'd had was a no hoper and was reduced to spares. A pity, but as luck would have it,I had kept the control which was popped in and worked perfectly ( pause to let out large sigh of relief )
I spun the valves through the tester and was amazed to see they were all 80 % plus, even the ECC85 - I therefore suspect this was not a heavily used set, especially in view of the lack of wear around the piano keys.
As I replaced the mains lead, I noticed a rather bulging, almost melted hunts cap, on the EF89 g2 pin ( 0.04) . Just for fun, I clipped it into my cap tester, where it read all of 169 pF !
On the basis that where there's one..... I replaced a similarly mis-shapen cap on the other IF stage. The set was now much more lively. At this point I would often replace all the other hunts, but I've noticed on a "good" one of these, it makes very little improvement. On a bad one it's simply a waste of good caps !!

As the speaker cloth looked a bit grubby, I gave it a gentle wipe over with some foaming cleanser, and treated the LS cut out from the back also. This removed a lot of "speaker shadow".
Then it was back into the cabinet, pop in a new magic eye ( oops - last one, must get some more ! ) and off for soak test.
Great sound from such a little set, and much better performance than the average 50's AM/FM box. They're a bit like buses these - there's bound to be another one along if you wait a while !!!

[JoshWard]

I have one of these myself (at last ). I managed to do it in one weekend, a lot of the rubber wiring was replaced but none of the capacitors were. It does work well on VHF but it is rather quiet on AM. Looks like its time to replace some caps! At least I can listen to Sounds Of The Sixties on Radio 2 (if I am not using the Ferguson 384U that is!) on it. Well worth buying one.

[JoshWard]

Unfortunately, mine is not as mint as yours! In fact in the past someone had tried to re-paint the gold front. You can guess what it looked like.............

[howard]

Hello Setsappeal,

Thats a great looking little radio, and a brilliant restoration, well done !

Howard

[Neil Breward]

One of my favourite chassis, though I prefer the woody VHF162 to its bakelite sister.

Those Hunts caps are a problem. Other than the AF coupler the two that seem to give the most irritating faults are the HT decouplers feeding:

1. The last IF stage with the ratio detector (which won't align properly if this cap is O/C).

2. The VHF tuner. (Low gain with instability).

Oddly I've found several examples in these positions completely O/C rather than leaky. Screen grid decouplers are next on the suspect list . . .

Cheers,
Neil

[Steve G4WCS]

Hi, good to see another aet back to life. I like the look of the VHF61 myself, and am just about to start one.
by "that " capacitor are you referring to the the blocker between the volume control and the output valve ?

are there any other "favourites" to change.
I dont want to start recapping it willy nilly, as you say it can be a law of diminishing returns.
Thanks

Steve

[Leon Crampin]

This set is also one of my favourites; having dealt with several examples I would make the following observations:

1. These sets hardly ever need realigning if the white locking paint is intact - assuming that resoration has not caused a great deal of disturbance. The FM core string sometimes needs to be adjusted in the curved slot on the drum to give reasonable calibration/band coverage, especially after an ECC85 change.

2. Hunts capacitors - dreadful. Replace any running at high voltages and preferably all of them if you don't want a noisy set. EL84 g1 coupling capacitor is a must.

3. EL84 cathode bias resistor will be out of tolerance - usually high. Shunt to correct value (strangely, the Erie carbon comp resistors don't subsequently drift a lot). With a new coupling capacitor, correct bias and a good EL84, check the voltage on g1 wrt earth. If this is >20mV, and rises as the valve heats over a period of minutes, the EL84 is gassy. This is quite common.

4. Sets with a poor AM performance generally suffer from leakage between the slider switch sections. The culprits are the switches which short out the AM IF tranformer sections on FM. The worst one is the switch which backs onto the one which changes the AF feedback resistor at the lower end of the volume control (on the FM slider). The spacing on these Plessey sliders is just too close if an adjacent contact, usually on the reverse of the wafer, carries HT. There is a work-around; either you can disconnect the feedback section, leaving the set on maximum feedback for best quality, or you can re-configure the switching to work correctly using spare sections - there are just enough. This fault can also gives a mysterious crackling, due to HT breaking through to the audio stages. I have not given component references as Trader and Bush data are different.

5. If you fix the switches and get a reasonable AM IF gain, the set will work well with its ferrite aerial. The bottom coupled external aerial connection is useless. The trouble is that this set has no aerial-rotator, so AM performance is patchy unless you keep rotating the set - hardly practical.

6. An EM84 masked down with black tape is a cheaper eye replacement if you re-wire the socket. If you have got everything right on FM, the eye will overlap on a local station - I fit a 3:1 attenuator in the FM feed to the eye. There should be very little difference in volume between AM and FM - if anything, FM is louder for a given setting.

7. There is a fatal error on the Trader sheet - the positions of the cores of the final FM IF transformer (ratio detector) are reversed. The Bush data is correct.

8. Scratchy audio with good electronics is often caused by (fish?) glue failure in the centering device of the Celestion loudspeaker. Repair with a little PVA on a fine stick, then apply DC to the 'speaker (just enough current) to hold the joint closed whilst the glue sets.

Phew! That should just about do, but they are very nice sets.

[yestertech]

Suspect this is getting OT - perhaps mod. can move this to a new post ? (specific sets ? or "the perennially popular VHF61" ? )
Leon, good to see you back on the forum at last !! How's the Motorised Philips coming along ?? Andy

[mikelect]

Thread closed see Pauls "sticky" at the head of this section