Quad FM1 Tuner. Replacing the Hunts capacitors - UK Vintage Radio Repair and Restoration Discussion Forum

Budgie61 · 16th Nov 2022, 12:41 pm

Split from this thread:-

https://www.vintage-radio.net/forum/...d.php?t=195952

I have a Quad FM1 tuner that has seen better days, but it works... kind of. I want to use it to practice replacing components namely the Hunts Mouldseal capacitors. I am new to this hobby and am getting confused with what i should use to replace them. There seems to be so many variables and I'm left scratching my head. Can someone who is in the know please help! I'm hoping for a list of the Hunts capacitors and what I would use to replace them.

Station X · 16th Nov 2022, 2:56 pm

Hello and welcome to the forums. See here:-

https://www.vintage-radio.com/repair...apacitors.html

and here:-

https://www.vintage-radio.net/forum/...ad.php?t=88767

Budgie61 · 22nd Nov 2022, 12:05 pm

Hi, and thanks for the welcome. I've seen those suggested links and I've seen what I think is right. But I guess I was hoping for reassurance on my choices.
Cheers Steve

Station X · 22nd Nov 2022, 12:22 pm

I'm not a Quad expert, but I've never had any problems with the modern yellow cylindrical polyester or polypropylene capacitors.

If you want a comprehensive list of replacement capacitors we'll need to know wht's fitted at present ie capacitance and voltage.

John Caswell · 24th Nov 2022, 10:29 am

Having done fair few of these here is my 2 pen'north
I always replace the Hunts caps with ceramic disc types readily available from the usual sources, generally with a 1KV rating so no problems there. Try to keep them in the same place as the originals plus keep the leads as short as possible. The caps in the RF tuner are a swine to get to and really need the IF strip removing for better access, and as the RF section does rely somewhat on stray capacity for tuning try to keep them in exactly the same positions. Check all resistors especially the two 82K in the IF strip and the two 120K around the detector (EB91) area. If you are careful you may not need to realign anything.

John

16th Nov 2022, 12:41 pm	#1
Budgie61 Diode Join Date: Oct 2021 Location: Chelmsford, Essex, UK. Posts: 2	Quad FM1 Tuner. Replacing the Hunts capacitors Split from this thread:- https://www.vintage-radio.net/forum/...d.php?t=195952 I have a Quad FM1 tuner that has seen better days, but it works... kind of. I want to use it to practice replacing components namely the Hunts Mouldseal capacitors. I am new to this hobby and am getting confused with what i should use to replace them. There seems to be so many variables and I'm left scratching my head. Can someone who is in the know please help! I'm hoping for a list of the Hunts capacitors and what I would use to replace them.

16th Nov 2022, 2:56 pm	#2
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 20,643	Re: Quad FM1 Tuner. Replacing the Hunts capacitors Hello and welcome to the forums. See here:- https://www.vintage-radio.com/repair...apacitors.html and here:- https://www.vintage-radio.net/forum/...ad.php?t=88767 __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

22nd Nov 2022, 12:05 pm	#3
Budgie61 Diode Join Date: Oct 2021 Location: Chelmsford, Essex, UK. Posts: 2	Re: Quad FM1 Tuner. Replacing the Hunts capacitors Hi, and thanks for the welcome. I've seen those suggested links and I've seen what I think is right. But I guess I was hoping for reassurance on my choices. Cheers Steve

22nd Nov 2022, 12:22 pm	#4
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 20,643	Re: Quad FM1 Tuner. Replacing the Hunts capacitors I'm not a Quad expert, but I've never had any problems with the modern yellow cylindrical polyester or polypropylene capacitors. If you want a comprehensive list of replacement capacitors we'll need to know wht's fitted at present ie capacitance and voltage. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

24th Nov 2022, 10:29 am	#5
John Caswell Hexode Join Date: Jul 2009 Location: Wokingham, Berkshire, UK. Posts: 435	Re: Quad FM1 Tuner. Replacing the Hunts capacitors Having done fair few of these here is my 2 pen'north I always replace the Hunts caps with ceramic disc types readily available from the usual sources, generally with a 1KV rating so no problems there. Try to keep them in the same place as the originals plus keep the leads as short as possible. The caps in the RF tuner are a swine to get to and really need the IF strip removing for better access, and as the RF section does rely somewhat on stray capacity for tuning try to keep them in exactly the same positions. Check all resistors especially the two 82K in the IF strip and the two 120K around the detector (EB91) area. If you are careful you may not need to realign anything. John