Fenman 2 Mains Transformer - UK Vintage Radio Repair and Restoration Discussion Forum

jetstream320 · 11th Dec 2009, 6:21 pm

I have a Pye Fenman 2 which has been professionally overhauled, all suspect capacitors replaced etc. and it is working very well. The only problem is that the Mains Transformer is running very hot. After a couple of hours it is too hot to hold a hand on the top. It probably doesn't help that the output valves are very close to it. I have a second Fenman 2,working but tatty,and this is exactly the same. Does any Fenman 2 owner know if this is normal, or do I have two transformers with shorted turns?
I think these sets sound much better than any Grundig!

Radio_Dave · 11th Dec 2009, 6:32 pm

I've got 5 and they all run hot and make the wax go all gooey. It's not helped by having the 2 output valves beside it

.

If it's been serviced and recapped I wouldn't worry.

David

Steve_P · 11th Dec 2009, 6:34 pm

Yes, they do get warm. And so do the Output Valves, it must be said. Not a risk, but pretty hot all the same.

Cheers,

Steve P.

jetstream320 · 11th Dec 2009, 6:46 pm

Thanks Dave and Steve,
I will stop worrying about it now.
Cheers,
Chris.

yestertech · 11th Dec 2009, 7:07 pm

Check what sort of EL84s are fitted. If you have ancient Mullards be suspicious. They can develop appreciable +ve grid volts after 30 mins ( or less ! ) of running. This increases the HT current of course.
Check for around 8.5 volts across the cathode resistor of each valve after 15 mins or so.
HT current in total on FM is given as 85mA although there is no easy way to measure this without 'surgery'

Andy

jetstream320 · 14th Dec 2009, 11:11 am

Thanks Andy,
The EL84's are ancient but they are not Mullard ones. They have got the name Pinnacle on them, but I guess they could have been made by Mullard. I will measure the currents anyway to be on the safe side. I have also noticed that there is melted wax underneath the transformer on the chassis so it is running pretty hot. The other set has old wax on the chassis as well.
Chris.

Radio_Dave · 15th Dec 2009, 1:36 am

Hi Chris,

All my Fenman II's came with a puddle of wax under the mains transformers. As I mentioned above, it never worried me, but I did have the confidence in knowing that I had personally changed all the cap and the output valves were in good condition.

Personally, as long as it has been serviced properly, I don't think you've got a problem, but it certainly won't do no harm checking the HT current, as suggested by Andy

jetstream320 · 15th Dec 2009, 2:19 pm

I have monitored the cathode voltage on the EL84's for over an hour, it stayed the same at exactly 9 volts. I also tested them and they are nowhere near a matched pair, one is ok but the other only draws half the Anode Current quoted in the Avo book, but it still sounds very good. I will look for a good matched pair in due course, and not worry about the puddle of wax.
Thanks Andy/Dave.
Cheers,
Chris.

11th Dec 2009, 6:21 pm	#1
jetstream320 Tetrode Join Date: Feb 2007 Location: Christchurch, Dorset, UK. Posts: 50	Fenman 2 Mains Transformer I have a Pye Fenman 2 which has been professionally overhauled, all suspect capacitors replaced etc. and it is working very well. The only problem is that the Mains Transformer is running very hot. After a couple of hours it is too hot to hold a hand on the top. It probably doesn't help that the output valves are very close to it. I have a second Fenman 2,working but tatty,and this is exactly the same. Does any Fenman 2 owner know if this is normal, or do I have two transformers with shorted turns? I think these sets sound much better than any Grundig!

11th Dec 2009, 6:32 pm	#2
Radio_Dave Nonode Join Date: Jun 2004 Location: Norwich, Norfolk, UK. Posts: 2,543	Re: Fenman 2 Mains Transformer I've got 5 and they all run hot and make the wax go all gooey. It's not helped by having the 2 output valves beside it. If it's been serviced and recapped I wouldn't worry. David

11th Dec 2009, 6:34 pm	#3
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: Fenman 2 Mains Transformer Yes, they do get warm. And so do the Output Valves, it must be said. Not a risk, but pretty hot all the same. Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

11th Dec 2009, 6:46 pm	#4
jetstream320 Tetrode Join Date: Feb 2007 Location: Christchurch, Dorset, UK. Posts: 50	Re: Fenman 2 Mains Transformer Thanks Dave and Steve, I will stop worrying about it now. Cheers, Chris.

11th Dec 2009, 7:07 pm	#5
yestertech Nonode Join Date: Dec 2002 Location: Coulsdon, Surrey, UK. Posts: 2,135	Re: Fenman 2 Mains Transformer Check what sort of EL84s are fitted. If you have ancient Mullards be suspicious. They can develop appreciable +ve grid volts after 30 mins ( or less ! ) of running. This increases the HT current of course. Check for around 8.5 volts across the cathode resistor of each valve after 15 mins or so. HT current in total on FM is given as 85mA although there is no easy way to measure this without 'surgery' Andy

14th Dec 2009, 11:11 am	#6
jetstream320 Tetrode Join Date: Feb 2007 Location: Christchurch, Dorset, UK. Posts: 50	Re: Fenman 2 Mains Transformer Thanks Andy, The EL84's are ancient but they are not Mullard ones. They have got the name Pinnacle on them, but I guess they could have been made by Mullard. I will measure the currents anyway to be on the safe side. I have also noticed that there is melted wax underneath the transformer on the chassis so it is running pretty hot. The other set has old wax on the chassis as well. Chris.

15th Dec 2009, 1:36 am	#7
Radio_Dave Nonode Join Date: Jun 2004 Location: Norwich, Norfolk, UK. Posts: 2,543	Re: Fenman 2 Mains Transformer Hi Chris, All my Fenman II's came with a puddle of wax under the mains transformers. As I mentioned above, it never worried me, but I did have the confidence in knowing that I had personally changed all the cap and the output valves were in good condition. Personally, as long as it has been serviced properly, I don't think you've got a problem, but it certainly won't do no harm checking the HT current, as suggested by Andy

15th Dec 2009, 2:19 pm	#8
jetstream320 Tetrode Join Date: Feb 2007 Location: Christchurch, Dorset, UK. Posts: 50	Re: Fenman 2 Mains Transformer I have monitored the cathode voltage on the EL84's for over an hour, it stayed the same at exactly 9 volts. I also tested them and they are nowhere near a matched pair, one is ok but the other only draws half the Anode Current quoted in the Avo book, but it still sounds very good. I will look for a good matched pair in due course, and not worry about the puddle of wax. Thanks Andy/Dave. Cheers, Chris.