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Wanted: Spare valve
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Return to top of page · Post #: 1 · Written at 7:51:00 PM on 19 April 2026.
	OliBHolmes Location: Nuriootpa, SA Member since 28 June 2025 Member #: 2734 Postcount: 79
Hello all, A bit of a specific request, But did anyone have a coke-bottle type AWV 5AS4? Thought I'd be a bit of a pedant and try to use only AWV valves for my '209. Thanks!! Oli ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ Unqualified, unsupervised, and inexplicably alive...

Return to top of page · Post #: 2 · Written at 11:52:54 PM on 19 April 2026.
	GTC Location: Sydney, NSW Member since 28 January 2011 Member #: 823 Postcount: 6948
One advantage of being a member of the HRSA is that you get access to the Valve Bank (which may have that valve).

Return to top of page · Post #: 3 · Written at 7:08:19 AM on 20 April 2026.
	OliBHolmes Location: Nuriootpa, SA Member since 28 June 2025 Member #: 2734 Postcount: 79
I went to my local HRSA valve bank, (Good ol' Aztronics!) but, unfortunately, no coke bottles. Heaps of the later type 5AS4! I nabbed a few of them, just in case. Oli ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ Unqualified, unsupervised, and inexplicably alive...

Return to top of page · Post #: 4 · Written at 7:43:42 PM on 20 April 2026.
	Robbbert Location: Hill Top, NSW Member since 18 September 2015 Member #: 1801 Postcount: 2253
I'm not sure what you mean about "coke bottle". I've seen the usual cylinder-shaped ones, plus a few of the older ones that look like an ordinary octal valve with the bulge in the middle, just bigger. The 5AS4 uses(wastes) an extra 5 watts for the filament, so I prefer to use a 5Y3G if possible. Depends on how much HT current you need.

Return to top of page · Post #: 5 · Written at 8:45:57 PM on 20 April 2026.
	Brad Administrator Location: Naremburn, NSW Member since 15 November 2005 Member #: 1 Postcount: 7622
The latter is the 'coke bottle'. ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ A valve a day keeps the transistor away...

Return to top of page · Post #: 6 · Written at 5:57:46 PM on 21 April 2026.
	Johnny Location: Hobart, TAS Member since 31 July 2016 Member #: 1959 Postcount: 605
Have sent you an email, Oli. JJ

Return to top of page · Post #: 7 · Written at 6:05:17 PM on 21 April 2026.
	OliBHolmes Location: Nuriootpa, SA Member since 28 June 2025 Member #: 2734 Postcount: 79
Just replied, thanks! ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ Unqualified, unsupervised, and inexplicably alive...

Return to top of page · Post #: 8 · Written at 4:32:57 AM on 22 April 2026.
	Brad Administrator Location: Naremburn, NSW Member since 15 November 2005 Member #: 1 Postcount: 7622
Photo uploaded. ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ A valve a day keeps the transistor away...

Return to top of page · Post #: 9 · Written at 9:16:10 AM on 22 April 2026.
	Robbbert Location: Hill Top, NSW Member since 18 September 2015 Member #: 1801 Postcount: 2253
Thanks Brad, the photo makes it obvious. I'd still use a 5Y3 instead.

Return to top of page · Post #: 10 · Written at 11:08:09 AM on 22 April 2026.
	Johnny Location: Hobart, TAS Member since 31 July 2016 Member #: 1959 Postcount: 605
Would not use a 5Y3 in place of a 5AS4 in a TV set. JJ

Return to top of page · Post #: 11 · Written at 12:59:10 PM on 22 April 2026.
	Marcc Location: Wangaratta, VIC Member since 21 February 2009 Member #: 438 Postcount: 5710
Caution is appropriate: 5Y3 Filament 2A Max DC output 125mA 5AS4 Filament 3A DC output 275mA Do not run 5Y3 side ways. Only one position you can do that.

Return to top of page · Post #: 12 · Written at 3:56:34 PM on 22 April 2026.
	OliBHolmes Location: Nuriootpa, SA Member since 28 June 2025 Member #: 2734 Postcount: 79
As you can see, the coke bottle 5AS4 I do have, has no getter! Yeah, I can't use a 5Y3, It's for a TV set! Has to supply B+ to 17 valves, among other things. Oli ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ Unqualified, unsupervised, and inexplicably alive...

Return to top of page · Post #: 13 · Written at 5:56:32 PM on 22 April 2026.
	Robbbert Location: Hill Top, NSW Member since 18 September 2015 Member #: 1801 Postcount: 2253
Didn't know this was for a TV, sorry about that. A 5AS4 will be the right valve for the job then. Isn't that a getter behind the black blob at the top?

Return to top of page · Post #: 14 · Written at 7:22:12 PM on 22 April 2026.
	OliBHolmes Location: Nuriootpa, SA Member since 28 June 2025 Member #: 2734 Postcount: 79
It is a radio forum.. my fault! That black blob is the getter! When I tested it on another of my TV sets, I got no rectification at all! completely down to air. Oli ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ Unqualified, unsupervised, and inexplicably alive...

Return to top of page · Post #: 15 · Written at 8:11:28 PM on 22 April 2026.
	Brad Administrator Location: Naremburn, NSW Member since 15 November 2005 Member #: 1 Postcount: 7622
Well, to be technical for a minute, a radio is not a telly but a telly is a radio. ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ A valve a day keeps the transistor away...

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