Murphy Acoustic Deluxe - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

G8vsjDave · 14th May 2018, 6:23 pm

Hmm, let me have a think about that Peter. Life here is just going into overdrive because my wife was told today that her hip replacement will be tomorrow. I’ll give it some thought and probably open a new thread – but no promises.
Dave

Focus Diode · 14th May 2018, 8:54 pm

I think I was a little unfair in my one time comment that Rank should have continued with their hybrid models on taking a look at an A816 many years ago. At that time I never encountered an A774! Was it Rank who advertised they were producing solid state B&W sets while most others still used valves?

FERNSEH · 14th May 2018, 9:53 pm

In 1972 the Rank-Bush-Murphy A816 was the only UK made large screen all transistor mono TV.

DFWB.

stuie319 · 15th May 2018, 12:46 am

It's been fascinating to read all these posts about people's experiences of the chassis. Especially from someone involved in the original conception!
I haven't had much opportunity to play with it, work really does get in the way of important stuff, but it does have an interesting fault.
After it's been running awhile it appears as though the front end is overloaded. It starts with vertical twitching at the top, and if left long enough ends up with complete loss of sync, then video, and sound.
The symptoms can be mitigated by either slightly off tuning, or attenuating the rf input. It's as though the rf agc is ramping up hugely.
It's years since I possessed freezer spray, but spying a tin at the NVCF I grabbed it. Hopefully the fault is thermal and this will help to locate it. The IF section is the least accessible bit of the chassis of course.....
The tube isn't excellent, but equally it isn't terrible either. We shall press on
Thanks for all the interest guys

Regards
Stu

14th May 2018, 6:23 pm	#21
G8vsjDave Pentode Join Date: Jul 2010 Location: Nottingham, Nottinghamshire, UK. Posts: 233	Re: Murphy Acoustic Deluxe Hmm, let me have a think about that Peter. Life here is just going into overdrive because my wife was told today that her hip replacement will be tomorrow. I’ll give it some thought and probably open a new thread – but no promises. Dave

14th May 2018, 8:54 pm	#22
Focus Diode Octode Join Date: Jan 2006 Location: Borough of Gateshead, UK. Posts: 1,420	Re: Murphy Acoustic Deluxe I think I was a little unfair in my one time comment that Rank should have continued with their hybrid models on taking a look at an A816 many years ago. At that time I never encountered an A774! Was it Rank who advertised they were producing solid state B&W sets while most others still used valves?

14th May 2018, 9:53 pm	#23
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Murphy Acoustic Deluxe In 1972 the Rank-Bush-Murphy A816 was the only UK made large screen all transistor mono TV. DFWB.

15th May 2018, 12:46 am	#24
stuie319 Pentode Join Date: Jan 2007 Location: Stockport, Greater Manchester, UK. Posts: 229	Re: Murphy Acoustic Deluxe It's been fascinating to read all these posts about people's experiences of the chassis. Especially from someone involved in the original conception! I haven't had much opportunity to play with it, work really does get in the way of important stuff, but it does have an interesting fault. After it's been running awhile it appears as though the front end is overloaded. It starts with vertical twitching at the top, and if left long enough ends up with complete loss of sync, then video, and sound. The symptoms can be mitigated by either slightly off tuning, or attenuating the rf input. It's as though the rf agc is ramping up hugely. It's years since I possessed freezer spray, but spying a tin at the NVCF I grabbed it. Hopefully the fault is thermal and this will help to locate it. The IF section is the least accessible bit of the chassis of course..... The tube isn't excellent, but equally it isn't terrible either. We shall press on Thanks for all the interest guys Regards Stu