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Old 13th Sep 2019, 10:01 am   #41
Synchrodyne
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Quite a bit more information on the Philips “Innoval” valve series and its Rimlock-to-noval transition may be found at these web sites:

https://www.radiomuseum.org/forum/ea..._innovals.html


https://www.radiomuseum.org/dsp_mult...s_innovals.pdf


No real surprises, but they provide confirmation of previous deductions.


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Old 13th Sep 2019, 10:35 am   #42
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

In the former article, the term 'glazed' is used too many times instead of 'fritted', suggesting it might have something to do with enamel (one of the designations appearing in the Philips code lists), which it probably doesn't.

Otherwise a very nice write up and some interesting reading.
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Old 13th Sep 2019, 11:08 am   #43
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Hmmm... Never mind, Philips seems to have used the term glaze themselves in the latter link.
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Old 13th Sep 2019, 10:59 pm   #44
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Synchrodyne's first post #41 link highlights the fact that VHF/FM broadcasting in West Germany got underway early and progressed smartly, with the Graetz 154W and 156W radios mentioned featuring 2x EF42 pentodes- it would be reasonable to assume that these were deployed as VHF RF amp and mixer/oscillator, raising the question of how this valve would compare with the EF91 and EF80 in various roles. It may have had a brief reign in VHF Band I TV RF and IF usage in the UK but UK VHF Band II FM broadcasting probably got into gear a little late for it. On the plus side, it has a notably high gm (plus the very short and direct internal connections of the Rimlock construction), on the minus side it has only one cathode-connected pin.
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Old 14th Sep 2019, 12:22 am   #45
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Some comment on EF42 performance relative to the EF91 and EF80 was provided in the recent thread “EF91 to EF80”, https://www.vintage-radio.net/forum/...d.php?t=157399,

I think that the best insight came from the valve choices for the Fitton (Ambassador)-BBC VHF AM-FM comparator receiver. In this both the EF91 and EF42 were used, the EF42 being chosen for situations where its very high slope was advantageous, including the oscillator, AFC reactance valve and the two limiters. It was also used for the RF amplifier, although it was said that had the EF80 or 6F1 been available when it was designed, they would have been even better for that role. The 6F1 was basically a 6F13 with two cathode pinouts and with the internal screen sharing a pinout with the suppressor grid as a consequence. With a single short production run special-purpose receiver, use of several generally similar valve types was not really a problem, whereas for larger-scale production, rationalization on just one would have been highly desirable.

Fitton used the EF91 as mixer. But where an autodyne mixer was required, then the EF42 was probably a better choice because it was a better oscillator. So for a two-valve front end, an EF42 RF amplifier and an EF42 autodyne mixer was logical, with the advantage that the same valve type was used in both positions. Once the EF80 became available, then that would have been the better choice for the RF amplifier, and that being so, it might also have been chosen for the autodyne mixer to achieve commonality, and perhaps on the basis that the RF amplifier improvement was worth more than the loss in mixer performance.

Lowther’s valve choices for its initial FM tuner model were also indicative. It had a 6BW7 (effectively a higher slope EF80) RF amplifier, EF80 IF amplifier and EF42 limiter. From that one could infer that the higher slope of the 6BW7 as compared with the EF80 was beneficial in respect of the RF amplifier (where a two-cathode pinout valve was strongly preferred), but not in respect of the IF amplifier, where stability considerations may have limited achievable gain. (Jason found the EF80 to be a slightly better FM IF amplifier than the EF91 simply because it had lower in-situ interelectrode capacitances, and so a higher stability threshold.) Presumably the very high slope of the EF42 could not be used to advantage in the IF amplifier, but it was useful in the limiter. Given that Lowther products were of the low production “hand-carved” type, valve rationalization would not have been a paramount concern.


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Old 14th Sep 2019, 1:53 am   #46
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Quote:
Originally Posted by Maarten View Post
Quote:
Originally Posted by kalee20 View Post
One thing I have noticed between B8A rimlock, and B9A noval (and B7G), the pins of B8A valves are hard and stiff, whereas the others aren't.

I can see the need for pins that bend, if the valve is knocked sideways in the valveholder then the pins bend rather than the glass breaks. And B8A valves are supported by the skirt anyway so the force is not taken by the pins. But given that bendy pins would not detract from the valve in B8A, and given that the alloy had already been developed for B7G, what did B8A have rigid pins? Or was it just cheaper?
The design of the glass base and pins was likely based on the older B8G base, so developed before the B7G.
The issue of pin stiffness and shortness of the internal links was addressed in the second link in post #41, https://www.radiomuseum.org/dsp_mult...s_innovals.pdf. See pages 5 and 6.

The stiff pins, some extended well upwards into the valve, were a specific feature of the Rimlocks, and one that Philips saw as an improvement on the B7G and American B9A structures. Thus it was carried over to the Innoval series, which was thus said to combine the best features of the Rimlocks and the novals. But Philips does appear to have reverted to the conventional B9A noval structure within a few years.

Notwithstanding that Philips developed the Rimlock form for its main domestic receiving valve series, it also started manufacturing B7G miniatures at about the same time as it started Rimlock production. The B7G range included not only valves for battery portable receivers, where minimal valve size was obviously important, but also industrial valves such as the EF91, EB91, ECC91 and so on. Presumably Philips simply followed the standard B7G pattern when it came to the pins and lower internal structure, and did not apply its Rimlock ideas to these valves.

As another facet to the Philips noval/Innoval story, it would be useful to find Philips’ initial release on its TV World Series valves. All but two of the initial range were on the noval base, so it would be interesting to see how this feature was presented as compared with its Australian Innoval material.


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Old 16th Sep 2019, 12:59 pm   #47
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Quote:
Originally Posted by Synchrodyne View Post
Quite a bit more information on the Philips “Innoval” valve series and its Rimlock-to-noval transition may be found at these web sites:

https://www.radiomuseum.org/forum/ea..._innovals.html


https://www.radiomuseum.org/dsp_mult...s_innovals.pdf


No real surprises, but they provide confirmation of previous deductions.
Two super links - thank you Steve!
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Old 16th Sep 2019, 7:34 pm   #48
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Yes, absorbing reading, and it helps to emphasise what sophisticated and precision components valves really were.

The article on innoval valves and the Rimlock-like fritting process reminded me about a UL41 in employment here, with its straight, shoulderless bulb- perhaps a late-production type and which, apart from its B8a base and small keying pip, could at first glance be taken for something like a UL84. Could it be that this overall diameter increase of around 2mm helped keep the temperature of this often hard-worked type reasonable, or maybe it simply meant that legacy B8a valve types could be processed with B9a jigs. I gather that there was a "middle-age spread" version of the PL81 with an expanded-diameter bulb section, supposedly to help reliability of this also hard-working valve.

(Excuse focus on this ad-hoc smartphone shot!)
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Old 16th Sep 2019, 9:46 pm   #49
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

I'm sure I have seen a similar B8A valve... But it brings the hard pin query back. If the glass base and the body were fused together with the B9A process, ie locally raised to the softening point of glass so they weld together, then there is the possibility of the pins moving fractionally out of position, which would mean they would need to be soft enough to bend back into alignment without fracturing the glass.
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Old 16th Sep 2019, 10:06 pm   #50
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Most B8A valves were obsolete before they started to be made in B9A style, but the UL41 is quite commonly available like that - Tungsram made lots of them. There must have been a healthy domestic replacement market, and they also appear to have been used in military equipment. Late UL41s have redesigned heaters which make them less liable to develop heater/cathode leaks, but they take quite a while to warm up as a result.
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Old 23rd Sep 2019, 3:45 am   #51
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

The UL41 was probably amongst the last of the main Rimlock series to have a noval successor, namely the UL84 of c.1955. Until then the UL41 would have served as the standard output valve for European radio receivers that used 100 mA series-string valves. The EL84, European noval successor to the EL41, had arrived a few years earlier. The UL84 (and PL84 and EL86) looked to have been more of a design challenge given that they needed to deliver full power at 170 volts on the anode, so that might have been one reason for the apparent delay as compared with the EL84. They required aligned screen grids to help keep screen grid current low and so total cathode current at a sanitary level. Not so much developing the technique, but enabling its reliable production at acceptable costs might have taken extra time. (It might have been more difficult to do it with high-slope pentodes, with their close grid spacings, than with lower slope beam tetrodes, where the technique was well established.)

There was a UL80 that was released quite early on. But the limited available information indicates that this was simply a 100 mA heater version of the EL80/6M5 Innoval (itself a noval version of the EL41), and was thus not configured for 170-volt HT operation. Where it was sold and used I do not know. It does not appear to have had an American registration. In similar vein there were the UCH80 and UF81, noval versions of the ECH80/6AN7 and EF81/6BH5. The UBC81 may also have been an early release, part of this group, but held back in Europe (in favour of the UBC41) until c.1954-55.


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Old 27th Sep 2019, 6:18 am   #52
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

The Philips initial release on the Australian Innoval series (2nd link in post #41) included a comparison between 6BD7 (EBC81) double diode-triode with the American 6AV6. The much lower diode-to-diode and diode-to-triode capacitances of the 6BD7, resulting from its internal screening, were stated to be advantageous in conventional domestic receiver circuits. (See page 10 pf the .pdf.) Given that the 6BD7 was essentially the EBC41 with a noval base, the same would have applied to the latter. The RMorg article (1st link in post #41) indicates that the EBC81 was not distributed in Europe until 1954 (I had guessed 1955), with the EBC41 offered until then. As well as for supply reasons, it appears that until the EBC81 was released, the British/European setmakers had technical reason to use the EBC41 rather than the 6AV6 or 6AT6. (I am assuming that the 6AT6 was similar to the 6AV6 in terms of its internal capacitances.)

It would appear that in Australia, the early Innovals, with the same internals as the initial Rimlock range, stayed in use until the end of the valve era, even though the later noval-only issues, such as the ECH81/6AJ8, were available. For example, the Audiosound AM100 wideband AM tuner, of c.1969, used a 6AN7 (ECH80, same internals as ECH42) as frequency changer.

The extended period over which novals progressively replaced Rimlocks in the European market did produce some interesting valve lines-up. The Ekco A182 export bandspread receiver provides a good illustration. I don’t know exactly when it was released, but c.1953 seems likely. Its valve line-up comprised 2 x EF41, ECH42, EBF80, EB91, 2 x ECC83, 2 x EL42, DM70 and EZ40.

The EF41, ECH42, EL42 and EZ40 were part of the original Rimlock range, and at the time were still current in Europe, with their noval replacements/counterparts not yet released in that region. Although the A182 might have been on the cusp of the ECH81 release. (The EF41, ECH42 and EZ40, but not as far as I know the EL42, already had Innoval counterparts in Australia by then.) The EBF80 was of necessity a noval valve from the start (and as the 6N8 was part of the initial Innoval range.) The EB91 had evidently superseded the EB41 in the European radio range. It [the EB91] had been part of the initial Philips World Series TV range, so it is logical that it also would have displaced the EB41 for new radio designs at about the same time. The ECC83 was a relatively new noval audio valve. It was somewhat different to the Rimlock ECC40, but a suitable, probably better successor for many AF applications. The DM70 was a new sub-miniature tuning indicator. There had been no tuning indicator in the Rimlock series, and the first noval version, the EM80 might still have been in the future, although not by much.

Reverting to the EBF80, this had been introduced in part to provide a combined IF amplifier, demodulator and AGC rectifier valve that allowed the use of conventional delayed AGC. Previously Philips/Mullard had recommended using the EAF42, with the pentode suppressor grid doubling as an AGC delay diode. But apparently this had not always worked very well. Perhaps ironically, in the A182, Ekco had used the EBF80 suppressor grid to provide a second delay for the RF AGC, the EBF80 AGC diode itself providing the initial delay for the IF AGC.


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Old 27th Sep 2019, 11:29 pm   #53
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Philips Technical Library Book IIIA, Data and Circuits of Radio and Amplifier Valves, Second Supplement, covered the radio valves developed during the Rimlock era, inclusive of the Rimlocks themselves, the battery miniatures and the very early novals. The English Edition was dated 1952, but as best I can tell, the original Dutch version covered developments up to the end of 1950.

The valves actually covered are listed in the index excerpt, attached. The section on the noval valves, following the Rimlock and miniature sections, started with the following commentary:

“In the foregoing a number of valves have been described which could be manufactured without difficulty in the Rimlock or miniature techniques. There are, however, valves which, because they employ more than eight electrode connections, cannot be made along these lines. Such valves are therefore made in a new 9-pin range, these being known as "Noval" valves. In appearance Noval valves are very similar to the miniature types, except that they are of larger diameter (max. 22 min) and have 9 pins, at 9 points of a decagon, the tenth point being vacant. This asymmetrical spacing of the pins, also employed in miniature, valves, obviates the need for a special pilot to guide the valve into its holder. The pitch circle diameter of the pins is 11.9 mm, which very nearly corresponds to that of the Rimlock valves. The Noval range so far comprises the double diode-pentodes EBF 80 and UBF 80, and the F.M. detector EQ 80, each of which is described in the following pages.”

That was quite prosaic, with no mention of applying Rimlock constructional techniques to the novals, nor any use of the “Innoval” name. It suggested that the noval base was to be used for valves where 8 pinouts were insufficient. That was certainly true for the E/UBF80, but not for the EQ80, which had started life as the Rimlock EQ40. There was no mention of the 6AN7 (ECH80), 6M5 (EL80) or 6BD7 (EBC81), all of which were in the initial Australian Innoval range, and all of which were (In)noval versions of existing Rimlock issues. Along with the 6N8 (EBF80), these were announced as the initial Australian Innoval releases before the end of 1950.

All of that underscores Philips’ regionally selective marketing approach. Australia got the Innoval range from the start. In Europe, the noval radio valves were presented as additions to what was basically a Rimlock range, with the implication that the radio valve offering would now be a mix of Rimlock and noval types. It was not stated that all future issues would in fact be novals (that would have been somewhat counterproductive from a marketing perspective), but it was likely the plan. By the end of 1950, Philips had decided that its standard TV valve range would be (mostly) on the noval base, and in fact the EF80 had already been mentioned late in 1949.

One imagines that there were internal Philips documents that delineated all of this in careful detail. But absent access to such, when a transnational organization uses different and potentially contradictory messages in different markets, then post facto outside observers are left to make deductions from whatever information is available. I think that we have now pretty much closed the loop on the Philips Rimlock/noval question that came up early on in the old “Valve Questions” thread of a decade ago, https://www.vintage-radio.net/forum/...591#post233591.


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Old 28th Sep 2019, 6:58 pm   #54
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Hi Folks, I did post, about 2 years ago, with pictures, a Mullard EF91 on a B9A base. Possibly a trial that escaped ?

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Old 1st Oct 2019, 2:20 am   #55
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

It could have been. We have only limited information about Philips’ intentions, so it may well have explored other possibilities that never came to commercial fruition, including novalization of the EF91.

What we do know or can reasonably deduce about Philips’ novalization programme is as follows:

By 1949, and perhaps during 1948, Philips had decided that it would adopt the noval base for mains-type domestic receiving valves. In detail:

1. Future radio and audio mains valve issues would be on the noval base, except for large output valves and large rectifiers. The first radio novals that were new types, and not reworks, (EBF80 and UBF80) were issued in 1949.

2. The planned standard range of TV valves would be on the noval base (with one or two exceptions).

3. For the Australian market – and perhaps only for this market – a small number of existing Rimlock valves would be reissued as novals under the Innoval name. The Rimlocks had not been released in Australia, so were effectively bypassed there. The Australian release also included new noval issues, such as the EBF80.

4. In the European case, the existing radio and audio Rimlocks would stay in place until either replaced by improved novals (e.g. ECH42 by ECH81, EF41 by EF89, EL41 by EL84), or in a minority of cases, noval versions of existing Rimlocks (e.g. EF40 by EF86, EBC41 by EBC81). In some of the latter cases this involved novals that had already been released in Australia, but had been held back in Europe. This process was completed by c.1955. Late changes were UL41 replaced by EL84, and EL42 replaced by EL85 (which was not quite the same as its predecessor).

5. The new TV valve range would replace the handful of “interim” TV Rimlocks, such as EF42 by EF80, UL44 by PL81, UL46 by PL82 and PL83.

6. The B7G base would be retained for battery portable valves, including new issues.

7. The Rimlock battery home radio series, DK40, etc., was not replaced by a similar noval series. Presumably the B7G battery series would in future be used for this application.

8. The B7G base would be retained for industrial valves.


If the EF91 was viewed as being primarily an industrial valve, then #8 suggests that Philips would not have had a strong reason for developing a noval version. For domestic receiving applications, it appears to have seen the EF80 as being equal to or better than the EF91 (and EF42) along most applied performance vectors, and good enough along those where it was not quite equal. At least that seems to have been the main thrust of this concurrent thread: https://www.vintage-radio.net/forum/...d.php?t=157399.

Nonetheless, given that development work often involves at least a preliminary look at ideas outside the scope of the initial commercial brief, someone in Philips might have looked at the EF91 as a candidate for novalization – e.g. with the same basic characteristics but with a second cathode pinout and an internal screen.

That notion that Philips had a distinct B7G industrial range is at least supported by indirect evidence. The French Cibot-Radio Miniwatt catalogue of 1956 February, available at: https://frank.pocnet.net/other/Philips/doc-cibot.pdf, listed several categories and subcategories of valves. These included the following:

Série Miniature – 9 broches (Noval)

Série Miniature – 7 broches pour postes “batterie”

Série Miniature – 7 broches pour postes “secteur”

Tubes Série “Rimlock”

As far as I know, “secteur” referred to the industrial sector.

Also I have on-hand a Mullard publication entitled “Valves for Industry and Communications”, Part One, second edition, 1949. This did include the domestic battery miniatures and Rimlocks, but in addition had several 6.3-volt B7G-based valves that did not usually appear in the domestic receiving lists, such as Philips Book IIIA. Included were the EF91, EF92, EAC91, EC91, ECC91, EB91, EL91 and EY91. Most of these were industry standards rather than Philips originals.

Whilst there was a specific industrial B7G series, where noval valves were required for industrial applications, these were simply drawn from the main noval series.

Re #2 above, it was noted that one or two of the TV valves were not on the noval base. One of those was the EB91 double diode, already in the industrial range. But for domestic applications, Philips had also introduced the Rimlock EB41 and UB41 double diodes. Presumably this was done in order to have a complete set of Rimlocks, no exceptions, even though the EB41 was quite similar to the EB91. For the TV case, apparently sanity prevailed, and rather than develop a noval double diode (say an “EB81”), Philips simply plucked the EB91 from the industrial range and made it part of the TV range. At about the same time the EB91 displaced the EB41 in the radio range, so that was an unusual case where a Rimlock was displaced by a B7G type rather than by a noval. (The UB41 was also eventually replaced by a B7G valve – UB91 or UAA91 – I am not sure which.)

Subsequently, there were a few other B7G interlopers added to the mostly noval radio/TV valve range. These included the EF97 remote cutoff and EF98 sharp cutoff car radio 12-volt HT pentodes. Possibly the smaller size of the B7G valves was seen as an advantage for what were size-constrained units. The frame-grid triodes, such as the EC95, developed for use as VHF TV RF amplifiers also had the B7G base. Perhaps this was advantageous to performance. Then there was the EH90 heptode, used as an FM sound locked oscillator demodulator. This was simply the American 6CS6 gated amplifier with a European number, so it could be that Philips decided to retain the original design on its B7G base rather than rework it as a noval.


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Old 1st Oct 2019, 2:42 am   #56
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Philips may have chosen to keep a valve like the 6CS6 on its B7G base with a view to selling them on the US market.

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Old 1st Oct 2019, 3:51 am   #57
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

The 6CS6/EH90 had an odd history, see: https://www.vintage-radio.net/forum/...6&postcount=15.

By the time Philips picked it up for use as an FM demodulator, the US industry was using later dual-control pentodes sych as the 6GX6 for FM demodulators of the dual-mode locked oscillator/passive quadrature type. Also, for the noise-gated sync separation function, the 6GY6 dual-control pentode and 6BU8 (& successors) double dual-control pentodes were used.

Just as the US industry initially used the radio frequency changer 6BE6 as a noise-gated sync separator, Philips used the ECH81 for the same purpose, then moving on to the ECH83, billed as both a 12-volt-HT car radio valve and a TV valve. That in turn was replaced by the ECH84 (noval base) at approximately the same time that the EH90 was introduced for the FM demodulation job. Later came the ECH200 on the decal base.

Amperex did offer quite a few of the Philips valves for TV use in the USA, and they were used by some major setmakers such as Zenith. Noval-based VHF pentodes were novel [groan] in the USA, where B7G was the norm for this type, but apparently the EF183 and EF184, under their respective American numbers, were regarded as offering desirable performance characteristics. I think that Amperex did offer the ECH200 in the USA, but I don't know about the EH90 - need to check that


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Old 1st Oct 2019, 4:57 am   #58
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Aye, it's straight-forward, though a lot of work, to document the family trees of all the valves, but the manufacturer's intent and motivation can only be guessed. And those are now the most interesting things.... what were they up to?

Of course, after all the price maintenance cartel business in the UK, we Brits are still not keen to trust valve makers.

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Old 2nd Oct 2019, 2:46 pm   #59
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

Quote:
Originally Posted by Synchrodyne View Post
Série Miniature – 9 broches (Noval)

Série Miniature – 7 broches pour postes “batterie”

Série Miniature – 7 broches pour postes “secteur”

Tubes Série “Rimlock”

As far as I know, “secteur” referred to the industrial sector.
"Secteur" is also French for "mains" and that would be the most probable interpretation in that particular context, coming right after a mention of "Miniature series -- 7 pins for battery sets".
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Old 3rd Oct 2019, 3:01 am   #60
Maarten
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Default Re: Valve Items - Philips/Mullard Rimlock-to-Noval Transition

First thing I thought of as well. Prtty sure it just means 'mains'.

Something else: I don't think EAA91 and EB91 were the same valve, they had a slightly different envelope, but I don't know whether that's significant (industrial range, copy of US valve, etc).

Another thing is the industrial range. I think the French used different colours of chalc for printing on the valve, depending in which range it was.

Also, Philips might have had an alternate (factory internal) definition for industrial range, in which most 7 pin valves (including special quality and CV derivatives of the xxx91 etc. series) are just ordinary receiving valves and the industrial range only consists of special valves (thyratrons, transmitting valves, etc.). This is suggested by the documentation on the different factory coding systems (the 2 lines of small characters at the bottom).
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