UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Philips210 · 17th Oct 2017, 10:03 pm

Hi.

I seem to recall some sets have two slugs in their IF transformers and are stagger tuned to give a broader response so tuning is not as sharp. The primary is tuned to about 2kHz below the nominal IF frequency and the secondary 2kHz above the nominal IF frequency. So peaking the transformer won't give the best performance.

David's circuit does look very useful though and is worth building. It's another good project to build but I must complete the loop aerial project first, I wish I had more time, it's been a busy year! It's small size and simplicity makes it handy to have around the workshop. Maybe a small modification so that a 470kHz IF as in many Philips sets can also be achieved.

Regards
Symon

17th Oct 2017, 10:03 pm	#19
Philips210 Nonode Join Date: May 2007 Location: Redruth, Cornwall, UK. Posts: 2,580	Re: 'I.F Alignment Aid' Hi. I seem to recall some sets have two slugs in their IF transformers and are stagger tuned to give a broader response so tuning is not as sharp. The primary is tuned to about 2kHz below the nominal IF frequency and the secondary 2kHz above the nominal IF frequency. So peaking the transformer won't give the best performance. David's circuit does look very useful though and is worth building. It's another good project to build but I must complete the loop aerial project first, I wish I had more time, it's been a busy year! It's small size and simplicity makes it handy to have around the workshop. Maybe a small modification so that a 470kHz IF as in many Philips sets can also be achieved. Regards Symon