Hacker RP75 back from the dead - UK Vintage Radio Repair and Restoration Discussion Forum

val33vo · 12th Jun 2018, 4:13 pm

I purchased a Hacker Super Sovereign as a non worker, pretty quickly narrowed it down to the complementary NPN germanium output transistor AC187 gone S/C. I have temporarily replaced it with a silicon NPN power transistor, amazingly the audio does not sound distorted ( I have not touched the bias pot as I have e bayed a genuine Mullard replacement, new OS ). The set works fine on FM MW LW but SW1 and 2 were very quiet, on studying the diagram it quickly became apparent they need an external antenna and sure enough a bit of wire shoved in the aerial socket brought them to life. I thought they might have had a space on the ferrite rod aerial but presumably ferrite is no good at higher frequencies than MW. Has anybody got a definitive answer to that?

westcliff · 12th Jun 2018, 7:15 pm

There should be an extending aerial for SW and FM reception.

Gus.

Radiocruncher · 13th Jun 2018, 8:34 am

The telescopic is unlikely to pick up anything as there are not many strong stations left on SW. A random length wire strung across the garden and clipped to the telescopic aerial should bring you some stations in especially after dark.

Regards

Graham

Hybrid tellies · 13th Jun 2018, 9:24 am

For my short wave listening I use a portable set with its telescopic rod aerial. Its true there are a lot less strong short wave signals about but its a case of listening at the right time. China Radio International, Radio Romania International, Voice of Turkey plus a few more do put out several English broadcasts a day which can be heard loud and clear.

12th Jun 2018, 4:13 pm	#1
val33vo Retired Dormant Member Join Date: Apr 2008 Location: Banffshire, Scotland, UK. Posts: 191	Hacker RP75 back from the dead I purchased a Hacker Super Sovereign as a non worker, pretty quickly narrowed it down to the complementary NPN germanium output transistor AC187 gone S/C. I have temporarily replaced it with a silicon NPN power transistor, amazingly the audio does not sound distorted ( I have not touched the bias pot as I have e bayed a genuine Mullard replacement, new OS ). The set works fine on FM MW LW but SW1 and 2 were very quiet, on studying the diagram it quickly became apparent they need an external antenna and sure enough a bit of wire shoved in the aerial socket brought them to life. I thought they might have had a space on the ferrite rod aerial but presumably ferrite is no good at higher frequencies than MW. Has anybody got a definitive answer to that?

12th Jun 2018, 7:15 pm	#2
westcliff Hexode Join Date: Jan 2011 Location: Essex, UK Posts: 396	Re: hacker RP75 back from the dead There should be an extending aerial for SW and FM reception. Gus.

13th Jun 2018, 8:34 am	#3
Radiocruncher Hexode Join Date: Dec 2013 Location: Torrington, Devon UK. Posts: 446	Re: Hacker RP75 back from the dead The telescopic is unlikely to pick up anything as there are not many strong stations left on SW. A random length wire strung across the garden and clipped to the telescopic aerial should bring you some stations in especially after dark. Regards Graham

13th Jun 2018, 9:24 am	#4
Hybrid tellies Nonode Join Date: Jan 2004 Location: 1966-1976 Coverack in Cornwall and Helston Cornwall. 1976-present Bristol/Bath area. Posts: 2,967	Re: Hacker RP75 back from the dead For my short wave listening I use a portable set with its telescopic rod aerial. Its true there are a lot less strong short wave signals about but its a case of listening at the right time. China Radio International, Radio Romania International, Voice of Turkey plus a few more do put out several English broadcasts a day which can be heard loud and clear. __________________ Simon BVWS member