Alba 461 long wave dead - UK Vintage Radio Repair and Restoration Discussion Forum

telstar · 15th Apr 2021, 2:29 pm

Hi. I have an Alba 461 radio from 1945/46 era where the long wave band has become inoperative. Upon examination, I have discovered the aerial and oscillator coils are in a screened box under chassis. The reason for inoperative long wave is that the primary winding of the aerial coil is o/c, but the secondary is intact. The coil wire is quite fragile, and I can not find the end. It must have had "green spot" problems. All the other bands work o.k!
Can the primary be by passed and fed in to the secondary, or can anyone suggest any other solutions, please?
Will send a picture next time.
Cheers
Mike

Julesomega · 16th Apr 2021, 11:18 am

You will be able to receive on LW without the aerial coupling winding, as long as the tuned winding resonates correctly. Tune to Radio 4 and peak the antenna trimmer: while you have your hand near the tuned circuit you should hear the signal quite well. Add a small capacitor, say 5-10pF between the trimmer/coil tuned circuit and an external wire aerial and it will work well enough although the sensitivity may not be optimum

telstar · 19th Apr 2021, 2:26 pm

Hi. Many thanks for your reply.
Here is a picture of the radio. It will be great to hear this functioning again. The secondary winding is intact, in fact the primary and secondary windings of the other bands are all o.k.
The radio itself looks like it was designed before WWII, to say it was introduced just afterwards.
Cheers
Mike

15th Apr 2021, 2:29 pm	#1
telstar Octode Join Date: Dec 2003 Location: Leeds, West Yorkshire, UK. Posts: 1,592	Alba 461 long wave dead Hi. I have an Alba 461 radio from 1945/46 era where the long wave band has become inoperative. Upon examination, I have discovered the aerial and oscillator coils are in a screened box under chassis. The reason for inoperative long wave is that the primary winding of the aerial coil is o/c, but the secondary is intact. The coil wire is quite fragile, and I can not find the end. It must have had "green spot" problems. All the other bands work o.k! Can the primary be by passed and fed in to the secondary, or can anyone suggest any other solutions, please? Will send a picture next time. Cheers Mike

16th Apr 2021, 11:18 am	#2
Julesomega Nonode Join Date: Dec 2012 Location: Stockport, Greater Manchester, UK. Posts: 2,117	Re: Alba 461 long wave dead You will be able to receive on LW without the aerial coupling winding, as long as the tuned winding resonates correctly. Tune to Radio 4 and peak the antenna trimmer: while you have your hand near the tuned circuit you should hear the signal quite well. Add a small capacitor, say 5-10pF between the trimmer/coil tuned circuit and an external wire aerial and it will work well enough although the sensitivity may not be optimum __________________ - Julian It's good here

19th Apr 2021, 2:26 pm	#3
telstar Octode Join Date: Dec 2003 Location: Leeds, West Yorkshire, UK. Posts: 1,592	Re: Alba 461 long wave dead Hi. Many thanks for your reply. Here is a picture of the radio. It will be great to hear this functioning again. The secondary winding is intact, in fact the primary and secondary windings of the other bands are all o.k. The radio itself looks like it was designed before WWII, to say it was introduced just afterwards. Cheers Mike Attached Thumbnails