Marconiphone T43DA Question - UK Vintage Radio Repair and Restoration Discussion Forum

Neil Purling · 15th Feb 2019, 8:12 am

I liked the look of the radio. However... It looks like the radio is barely a superhet.
radiomuseum lists it as having only 4 valves: UCH81, UF89, UL48 and a UY85 rectifier.
As there is no UBC8* it suggests that: A) It's relatively insensitive. B) It uses the UF89 as a regenerative detector or.. C) It uses a solid-state diode.
I had something like this as a late example of those 'Little Maestro' clone kit radios. A late example that had a mix of minature valves and Mouldseals. It produced second-harmonic images of stations & there was a trimmer to set the regeneration level.

snowman_al · 15th Feb 2019, 8:33 am

Hi Neil,
Answer is B. Leaky grid detector.
From memory there is an extra winding on the IF coil and a trimmer to adjust the regen. In the middle at the rear? Of course you can make it quite sensitive, but not over the whole band...
Also the volume control is not in the AF path?
Yes a very 'cheap' second set idea perhaps?
Alan

Neil Purling · 15th Feb 2019, 9:04 am

In my example of the design If you set the trimmer to bring up Radio 4 on LW it howled like a unruly child when switching back to MW.
With only two domestic stations I guess this sort of stripped down design was okay as a second-set.
I dunno if you could have got Luxembourg at night if it had been passed on to a teenager in later years. It was the images that were such a pain in my brief experience of the kind.
I don't see that the Marconi would have been much better than the kit version of the design I sampled.
The T43DA does look good & concealing the wave-change switch behind the badge is a great touch.

15th Feb 2019, 8:12 am	#1
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,086	Marconiphone T43DA Question I liked the look of the radio. However... It looks like the radio is barely a superhet. radiomuseum lists it as having only 4 valves: UCH81, UF89, UL48 and a UY85 rectifier. As there is no UBC8* it suggests that: A) It's relatively insensitive. B) It uses the UF89 as a regenerative detector or.. C) It uses a solid-state diode. I had something like this as a late example of those 'Little Maestro' clone kit radios. A late example that had a mix of minature valves and Mouldseals. It produced second-harmonic images of stations & there was a trimmer to set the regeneration level.

15th Feb 2019, 8:33 am	#2
snowman_al Octode Join Date: Dec 2018 Location: Llandeilo, West Wales, UK. Posts: 1,092	Re: Marconiphone T43DA Question Hi Neil, Answer is B. Leaky grid detector. From memory there is an extra winding on the IF coil and a trimmer to adjust the regen. In the middle at the rear? Of course you can make it quite sensitive, but not over the whole band... Also the volume control is not in the AF path? Yes a very 'cheap' second set idea perhaps? Alan __________________ Never Leave Well Enough Alone...

15th Feb 2019, 9:04 am	#3
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,086	Re: Marconiphone T43DA Question In my example of the design If you set the trimmer to bring up Radio 4 on LW it howled like a unruly child when switching back to MW. With only two domestic stations I guess this sort of stripped down design was okay as a second-set. I dunno if you could have got Luxembourg at night if it had been passed on to a teenager in later years. It was the images that were such a pain in my brief experience of the kind. I don't see that the Marconi would have been much better than the kit version of the design I sampled. The T43DA does look good & concealing the wave-change switch behind the badge is a great touch.