PYE FenMan 11, saleroom find.

[paulsherwin]

A number of large British sets had this dual speaker arrangement. It spreads the soundstage, and the slightly different speaker characteristics give a pseudo stereo effect.

[Synchrodyne]

Re the dissimilar pair of main speakers and the reason therefor, there is a brief mention of the benefits in this thread: https://www.vintage-radio.net/forum/...d.php?t=122277. The attached excerpt from Gilbert Briggs’ “Loudspeakers” book also provides some background.

A curiosity question – how long did the Pye FenMan I and FenMan II stay in production? As best I can determine, both were introduced mid-1955, along with the HFT111 hi-fi FM-AM tuner that used a close relative to the FenMan II RF circuit. The HFT111 gave way to the HFT113 Mozart around 1960-61, judging from the HFYB listings, so that may have marked a production change point for Pye that saw the end of the FenMan models. That said, I don’t know whether the HFT113 was derived from the HFT111, or a different design, perhaps derived from the FM-only HFT108 Mozart model.

Cheers,

[Techman]

Re, post 21.

That sounds a likely reason. I was assuming that it must be to do with a difference that Pye must have found between the two makes of speaker by conducting tests. I just find it interesting that you could potentially find either of the makes of speaker in a different make (or even another Pye with a single speaker) of radio and to expect the same performance, or perhaps the speaker manufacturers would not be expecting their particular speaker to perform with say slightly less bass than its opposite number.

I suppose that there could be a contract with one manufacturer to supply a standard speaker, but this manufacturer when asked to perhaps 'dope' a speaker to give a different frequency response, couldn't come up with the goods, so they had to use a different manufacturer.

Perhaps I'm just over complicating the thinking behind what the actual reasoning was?

Edit: Ah Synchrodyne, you posted as I was typing this post, thanks. Trader service sheet dated January 1957 says the release date was May 1955.

[Techman]

The chassis of the radio has now been moved from the table and into the radio room where I've managed to fit it onto the last remaining space on the work bench. Hopefully I should now be able to get down to the serious stuff.

[Radio_Dave]

Not all Fenman II's have a ferrite rod aerial and I don't think it's on the service data. However, I've never seen one with a LW coil on it.

Has it lost it's original volume potentiometer? The original had a something like a 300R tap on it and will be difficult to replace.

David

[stevehertz]

Originally Posted by Techman

On a couple of knobs, I actually pushed the knob slightly further on, which was now possible with the chassis being pushed further forward with the fixing screws now being removed. This may have helped break the joint, but had the disadvantage of closing up the last of the available gap making it more difficult to get a grip on, or getting leverage from behind the knob and it now also had a longer length of shaft for it to be removed from. I also used a method of breaking the seal whereby I turned the knob to the end of its travel then turned it just that touch more so as to stress the joint and flex the sprung skirt ring slightly, then turning it to the other end of its travel and doing the same, this needs extreme care and a sixth sense for just how much force to apply.

You were on dangerous territory there, stressing those knobs. They're like Spangles (sweets - remember them?) and will shatter at anything. But clearly you have the midas touch as you got them off safe and sound. Well done. Oh, also, I never use WD40 on plastic or rubber items. It contains petroleum products that can soften/damage such items - I've experienced it. I always use a pure silicon based lube for such purposes.

[Techman]

Thank you to all who have posted comments, advice, information and opinions.

I’d noticed that on the pictures of the chassis of this model that I’d looked at online that there was no ferrite rod aerial shown and had completely forgotten to mention it. I wonder if this was a later addition or a special order option? The date on the main smoother is ‘Mar 57’. That was well spotted as regards to the volume potentiometer replacement and the lack of the loudness tap. I’ll have to have a closer look at that and look for where the wire from the tap is connected now. The original pot type won’t be difficult to replace, it will be impossible to replace.

Shatter like Spangles! Ah yes, I remember spangles, square with a round dip in the middle, came in packets. I’ve never been much of a sweet eater, even as a child, but I remember spangles and they were one of the few sweets that I actually liked – don’t they make them anymore? I’ll be using some silicon grease on the shafts when I re-fit the knobs permanently.

I did some work on the radio earlier, replacing both output valve grid coupling capacitors C77 and C78. I also replaced the ‘waxy’ C71, mainly due to it getting in the way of the removal of the other two capacitors and its ‘waxyness’ was annoying me as it kept getting on my fingers while I was trying to remove them, so I removed it first, replacing it with a new one afterwards. The two black Hunts C77 and C78 were leaky at 5 meg even on a DVM and would have been a lot worse with HT on one end. The ‘waxy’ wasn’t quite as bad but needed replacing anyway – photos below.

I then replaced the mains lead. I don’t generally worry too much about two core mains leads on these types of radio as there’s no metal parts to be touched on the outside of the set. It could be argued that the chassis could be touched through aerial etc. apertures in the back panel, so wouldn’t comply to modern standards, but I tend to leave as designed. However, I had a nice thee core mains lead to hand that I must have cut off something at some time. It was black, was a decent length with the modern colour coding on the conductors and had a moulded on plug fitted – not quite vintage but now fitted. The set now has an earth and would probably pass a PAT (test), if it ever needed one - but that would be another discussion for another time and another place.

I had a look for C75 and noted that it was in a particularly awkward position, but it will be replaced along with possibly the one meg and half meg resistors in the eye circuit if it turns out they’ve risen in value by very much.

I then temporarily slid the chassis back into the cabinet and connected a bit of wire to the FM dipole socket and applied power. The valves warmed up and once tuned into a VHF station, I was greeted with superb audio with bags of volume. I tuned round on the other bands and the radio proved to be very lively. There was then some loss of volume which turned out to be to do with movement of that ‘special’ output transformer. It’s rather bigger than the original so is only able to be held on one side with a single fixing bolt which lets it move about a bit. This was causing it to short on something when it’s moved, so I need to look into what’s going on here and improve the fixing – some will say that transformer is wasted in this set. As I let the set run, another small issue showed up in the shape of dirty pin connections in the VHF tuner valve base. A quick wiggle of the valve sorted this, but proper cleaning will be carried out later.

I let the set run for an hour or so and listened a whole radio show and the performance and sound quality was almost as good as perfect. There were no bangs, no smoke or smells and the mains transformer was hardly warm to the touch. It’s debatable whether further cap changing will realistically make any difference to this sets performance and in the old days of the radio repair workshop, this job would have been wound up and the bill written out ready for the customer to collect the set. Believe it or not, I haven’t taken any voltage measurements yet, but I will be doing so later and will be doing certain tests to decide whether any further parts need replacing other than those connected with the ‘eye’ and the AGC line, which I’ll likely replace anyway. While I was tuning round on the set this time, I noticed that the magic eye was working to a small extent, but I think we can improve on things with a little more work. By their very nature, many of these paper capacitors would probably have been slightly leaky when they were brand new and first fitted in this radio back in 1957. It’s just the ones in critical positions that as they become worse with age, end up causing major problems, the rest just get on with doing what they’re supposed to do – in most cases. I’m not saying that none of the remaining capacitors in a set like this will need replacing, what I’m saying is that the ones that need to be replaced to improve on the sets operation will be replaced, and the ones that don’t, won’t be, just like it would have been done in a proper old school repair shop back in the day. I would, however, agree that a job on a radio like this nowadays is a bit more of a restoration than the straight forward repair that it would have been back then.

[stevehertz]

Re the two different speakers, it's my own view that on appraisal by Pye they found that both speakers showed merit, with one having say more bass while the other perhaps a clearer mid range, extended HF, that sort of thing. So, when paired together, they complimented each other to give a more extended, smoother, clearer response. Paul, I don't really get the pseudo stereo effect argument especially as they are so close together, and stereo, although it existed, was not really on peoples' radar at that time, and we are talking about a mono set; same signals to both speakers.

[paulsherwin]

Obviously the arrangement doesn't produce any approximation of true stereo, but it does mean that different frequencies peak at different positions on a (small) soundstage. The effect is much more subtle than simply splitting off the bass and treble. My Ekco A277 has this arrangement, and it really does sound better than a single speaker.

[stevehertz]

I agree with that.

[Takapuna]

These are indeed excellent sets. There's very little FM signal where I live (most unfortunate for someone with a radio collection) and the FenMan II is one set that pulls in a number of stations with little effort. I guess the EF80 RF amp comes into its own here, although I still need a short length of opened-out twin-flex in the socket when downstairs!

Does anyone know if the similar Pye Hi-Fi tuners were derived from the radio or vice-versa?

The fragile knobs have already been covered and I was well aware of their delicate nature when working on mine. All the hints and tips to do with the radio came from you good folk on the forum...so thank you everyone for these... However, armed with four complete carefully-removed knobs, no one mentioned anything regarding pushing them back on again! Following my efforts to remove them they weren't by any means a tight fit on the shafts but I still managed to break one (Spangles indeed!). It broke in such a manner that outer ring parted from the shank, leaving me with a complete tubular collar ( the part you turn with your fingers) and a mushroom shaped other part. I was lucky in that the break was clean and the two parts would mesh together again perfectly. Therefore I re-engaged the parts and stood them vertically on the knob end and filled the space within with epoxy resin. I gave the other knobs the same treatment too, even though they had not failed. Such treatment is invisible. The last thing I did was to remove the metal spring clip and slide down the shank as many reasonably tight fitting O-rings as needed until the knob was a nice fit on the control spindles once more without being too tight. I hope this may help others, if only to warn regarding the dangers pushing knobs back on again just when you though you'd won!

[Techman]

These sets really to receive well on VHF/FM. The job on mine has been wound up for now and the set is all back together with magic eye working and I'm listening to it as I type. The sound is very good but I would say that it's not quite as 'bright' sounding as the Grundig 3028 that I also have, but nothing wrong with that. I nearly always grease the shafts of knobs very slightly before re-fitting them if they've proved to be a very tight fit. It's been mentioned in the past that some greases 'may' react with the plastic of the knobs. I've no evidence myself that this is the case, but it's certainly something to keep in mind, hence I tend to use silicon grease.

These are a very nice radio that's sadly let down by poor quality knobs and plastic dial glass that the printing will come off at the drop of a hat, but overall, very good. I just need to polish out some of the scratches on the case and that will be it.

[Boater Sam]

It would be grand if we had a forum member who has a 3D printer and was prepared to knock out a few sets of knobs.....................................

I'm still looking for a white outer knob for a Murphy BA 228 after 3 years and I am sure that there are many sets needing just a knob to complete.

[Synchrodyne]

Originally Posted by Takapuna

Does anyone know if the similar Pye Hi-Fi tuners were derived from the radio or vice-versa?

My guess, and it’s only that, is the HFT111 FM-AM tuner was designed in parallel with the FenMan II radio receiver, with as much commonality as was reasonably possible.

From post #23, the FenMan II was released in 1955 May. The earliest reference I have to the HFT111 is in Wireless World 1955 October. It was a passing reference to its permeability tuning on FM and not a new model announcement, so it had probably been extant for a few months. The HFT111 was listed in HFYB 1956.

I don’t have a full schematic for the HFT111, but as best I can determine it was very similar to the RF section of the FenMan II. Whereas the latter used one diode in the EBC41 to provide delayed AM agc, the HFT111 might have used the EABC80 triode connected as a diode, but I am not 100% sure about this.

The Mozart HFT108 FM-only tuner came later. It was first listed in HFYB 1959, so it might have been released in later 1958. It was a bit different, and perhaps in some ways a step back from the HFT111 FM section. It had a two-gang, capacitively tuned front end instead of the three-gang permeability tuned type of the FenMan II and HFT111. The ECF80 triode was used as an AFC reactance valve, rather than as an oscillator, which meant that the pentode section was used as a self-oscillating mixer, not a separately-fed mixer. In the three-stage IF strip, the 2nd stage, unencumbered by any AM requirements, was used as an amplifier/limiter, so that might have been an improvement.

The Mozart HFT113 was an FM-AM (MF-only) tuner in the Mozart case, but I have never seen any information about its circuitry. It was first listed (without the HFT113 designation) in HFYB 1960, alongside the HFT111, and then with its designation in HFYB 1961, by which time the HFT111 had gone. By HFYB 1963, the FM-only model had become the HFT109 (my guess is that it was modified to have an MPX outlet). By HFYB 1964 the HFT113 had gone, and that was the last year that the HFT109 was listed.

The 3-gang front end – not common in British valve-era practice - coupled with the 3-stage IF strip and Foster-Seeley discriminator, and close attention to detail (something that you’d expect for the hi-fi tuner market) would have contributed to the reported good FM performance of the FenMan II (and presumably of the HFT111). With a pentode RF amplifier, the quieting curve might have been a bit behind that of the FenMan I (with ECC85 front end) at very low signal levels, but for most purposes that would not have been significant. For example, many first generation FM hi-fi tuners had pentode RF amplifiers, including the original Leak Troughline. On paper at least, AM performance should have matched that of a good standard circuit (e.g. ECH81, EF41, EBC41); notably Pye retained delayed agc on AM, something that many other makers were happy to abandon on their early FM-AM receivers, probably cause the standard valve line-up did not easily cater for it.

Cheers,

[Takapuna]

Thanks Synchrodyne.

Your guess makes good sense to me.

One other observation is that the FenMan I was named that way from the start. Maybe the base model would have been simply a FenMan (rather than a Fenman I) if the better model, the FenMan II, had been an opportunistic derivative from the tuner rather than a planned product.
Just a thought...

Phil.