Frame Grid Valves

[brunel]

A slightly grubby document from 1960.

[boxdoctor]

Thanks for that interesting doc. Brunel. I remember these valves coming out, and the difference in sensitivity of the new T.V.s fitted with the PCC189 was remarkable. They were a substantial advance in valve technology, of that there is no doubt.
I love the clear, precise English in which the article was written, and you can almost 'hear' the voice of the man who used to do the commentaries on the Mullard promotional films!. One of my workmates modified a GEC BRT 400 commmunication receiver to use an EF183 as the R.F. amplifier. BIG difference, especially above about 15 Megs.Happy days!. Tony

[Synchrodyne]

Originally Posted by boxdoctor

I love the clear, precise English in which the article was written, and you can almost 'hear' the voice of the man who used to do the commentaries on the Mullard promotional films!.

Yes, it was very nicely written. But back then that was more the norm. I am not familiar with the Mullard commentaries, but I can imagine the article being read with nicely rounded vowels (which maximize intelligibility) and perhaps down towards the old BBC WS newsreading speed of 120 words/minute.

Re the frame grid valves themselves, television receivers seem to have been the main beneficiary where consumer equipment is concerned, with occasional use elsewhere, such as hi-fi FM tuners and some professional/semi-professional HF receivers.

As well as the four mentioned in the article, the range would have included the UHF TV valves EC86 and EC88 (and their “P” counterparts.)

The prior existence of frame-grid special quality valves is mentioned. Was the E180F one of these?

Cheers,

[murphyv310]

A very good read, and so nicely done. Indeed these frame grid valves were a revelation. One set come to mind is the Thorn 980/981 series 405 line sets, it has a low valve count but the sensitivity of the set is literally quite amazing.

[OErjan_S]

over on another board a chap started experimenting with these for regen radios, he developed a design that is amazingly sensitive and the selectivity is amazing if made right.
hellenedyne is the name if you want to have a look here are the two papers.
http://home.comcast.net/~phils_radio...edyneNotes.pdf
http://home.comcast.net/~phils_radio...ellenedyne.pdf
http://home.comcast.net/~phils_radio...s/Theoflex.pdf

[Aerodyne]

A very informative article, Brunel. Of course I knew about frame-grid valves, but the details explained here are new to me and most enlightening.
Thanks for sharing this with us.
-Tony

[valvekits]

I found a nice little audio use for these valves when I modified one of my CD players last year.


Eddie