View Single Post
Old 7th Jun 2022, 7:17 pm   #1
vinrads
Dekatron
 
Join Date: Feb 2009
Location: Chesterfield, Derbyshire, UK.
Posts: 3,761
Default Pioneer TX 7500 tuner repair

This tuner came in from a friend ,it belonged to a good friend of his , who is suffering from terminal lung cancer ,so this one took priority , on plugging in I was greeted with the usual fm noise as if it was working ,I soon found out it wasn't , there was 12 volts on the tuning heart , so remover the module ,tied the tuning drum down so I didn't have to re string it , the rf amp transistor read ok , just to be sure applied a strong sig to the output of that stage ,still no sig , next step checked if the osc was running and tuning with the scope all ok , luckily the mixer transistor wasn't to bad to get at ,having removed it 2SC535 ,it was found to be oc all round , fitted a replacement now we have stations , you do need a 100 watt iron to remove the screening , It is now with the owner a small thing that made him happy for a while . Mick.
Attached Thumbnails
Click image for larger version

Name:	IMGP0009 (5).jpg
Views:	250
Size:	80.6 KB
ID:	258584   Click image for larger version

Name:	IMGP0010 (5).jpg
Views:	236
Size:	74.1 KB
ID:	258585  

Last edited by vinrads; 7th Jun 2022 at 7:26 pm.
vinrads is offline