Bush VTR175. Where's Radio 4? - UK Vintage Radio Repair and Restoration Discussion Forum

Avid_Nerdlinger · 18th Nov 2020, 5:16 pm

Got a Bush VTR175 (eBay £7.40) it needed a good clean and is still a bit rusty and stained but I think it was a good radio once and it performed quite well for me until it started going intermittent on MW and LW. I took the wave change switch off and cleaned it but the problem persisted. I tried buzzing the MW/LW RF mixer/osc transistor (2SC929) and found it had... a broken leg. I might have broken it while prodding it with the DVM probe but it must have been on its way out, possibly due to corrosion or the 8V DC adapter which was attached to the battery terminals (should be 6V) when I got it. I replaced the transistor with a Chinese 901 from a kit and now there still appears to be a problem with the wave change switch, perhaps I reassembled it wrong, don't think so though.

The weird thing is I can't get anything on MW but I can get a remarkably good signal for RTE1 (252kHz) on LW in about the right place on the scale but nothing at 198kHz where BBC R4 should be really strong. FM is all OK.

I should revisit the wave change switch next but I've spent way too much time on it lately and this radio is probably just a knackered white elephant so I might put it to one side for now.

murphyv310 · 21st Nov 2020, 5:33 pm

The replacement transistor could be faulty of course. Sounds like it's not oscillating properly and cutting out.
If course it could be even something else but covering your tracks is a good idea. Most silicon npn transistors will work even a BC108 will do.

18th Nov 2020, 5:16 pm	#1
Avid_Nerdlinger Pentode Join Date: Apr 2019 Location: Durness, Sutherland, UK. Posts: 108	Bush VTR175. Where's Radio 4? Got a Bush VTR175 (eBay £7.40) it needed a good clean and is still a bit rusty and stained but I think it was a good radio once and it performed quite well for me until it started going intermittent on MW and LW. I took the wave change switch off and cleaned it but the problem persisted. I tried buzzing the MW/LW RF mixer/osc transistor (2SC929) and found it had... a broken leg. I might have broken it while prodding it with the DVM probe but it must have been on its way out, possibly due to corrosion or the 8V DC adapter which was attached to the battery terminals (should be 6V) when I got it. I replaced the transistor with a Chinese 901 from a kit and now there still appears to be a problem with the wave change switch, perhaps I reassembled it wrong, don't think so though. The weird thing is I can't get anything on MW but I can get a remarkably good signal for RTE1 (252kHz) on LW in about the right place on the scale but nothing at 198kHz where BBC R4 should be really strong. FM is all OK. I should revisit the wave change switch next but I've spent way too much time on it lately and this radio is probably just a knackered white elephant so I might put it to one side for now. Attached Thumbnails

21st Nov 2020, 5:33 pm	#2
murphyv310 Dekatron Join Date: Sep 2006 Location: Kilmarnock, Ayrshire, UK. Posts: 5,422	Re: Bush VTR175. Where's Radio 4? The replacement transistor could be faulty of course. Sounds like it's not oscillating properly and cutting out. If course it could be even something else but covering your tracks is a good idea. Most silicon npn transistors will work even a BC108 will do. __________________ Cheers, Trevor. MM0KJJ. RSGB, GQRP, WACRAL, K&LARC. Member