Hacker Mayflower II - PSU Electrolytics. - UK Vintage Radio Repair and Restoration Discussion Forum

Nanozeugma · 9th Apr 2018, 1:29 pm

I have recently acquired a working (after a fashion) Maylower II.
The problems it has are:
Hum (variable).
Distortion.
Instability (guessing here, as it sounds like "motor boating" for a bit when starting up from cold).

Regarding the power supply electrolytics...
Someone has been here before me and stuffed the original 50+50 mfd main reservoir / smoothing cap with two small modern caps inside the old can.
If possible, I would prefer to fit a new can instead of this approach, I can get one (50+50uF 500V) for about £10 and may do this.
However...
The subsidiary can (50+50uF 200v) is quite small and I cannot source a replacement. Also, the can would, I think, be too small to stuff with two modern components.
The only alternative would seem to be to leave the old can in situ to preserve appearance and fit new caps under chassis... comments?

I am currently in the process of ordering replacements for all the old low voltage electrolytics and TCC Supamold interstage caps etc, these will all meet their maker (figuratively speaking) in due course.

paulsherwin · 9th Apr 2018, 1:55 pm

Many people routinely fit replacement caps under the chassis, including me. I'm not a big fan of capacitor restuffing - it's just a matter of personal preference, and there will be a range of opinions.

60 oldjohn · 9th Apr 2018, 2:37 pm

Have you checked the voltage from the rectifier, I would expect it has seen better days. If needed can be replaced with silicon bridge rec + resistor.

John.

9th Apr 2018, 1:29 pm	#1
Nanozeugma Heptode Join Date: Nov 2017 Location: London, UK. Bury, Lancashire quite regularly :) Posts: 611	Hacker Mayflower II - PSU Electrolytics. I have recently acquired a working (after a fashion) Maylower II. The problems it has are: Hum (variable). Distortion. Instability (guessing here, as it sounds like "motor boating" for a bit when starting up from cold). Regarding the power supply electrolytics... Someone has been here before me and stuffed the original 50+50 mfd main reservoir / smoothing cap with two small modern caps inside the old can. If possible, I would prefer to fit a new can instead of this approach, I can get one (50+50uF 500V) for about £10 and may do this. However... The subsidiary can (50+50uF 200v) is quite small and I cannot source a replacement. Also, the can would, I think, be too small to stuff with two modern components. The only alternative would seem to be to leave the old can in situ to preserve appearance and fit new caps under chassis... comments? I am currently in the process of ordering replacements for all the old low voltage electrolytics and TCC Supamold interstage caps etc, these will all meet their maker (figuratively speaking) in due course.

9th Apr 2018, 1:55 pm	#2
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,944	Re: Hacker Mayflower II - PSU Electrolytics. Many people routinely fit replacement caps under the chassis, including me. I'm not a big fan of capacitor restuffing - it's just a matter of personal preference, and there will be a range of opinions.

9th Apr 2018, 2:37 pm	#3
60 oldjohn Dekatron Join Date: Dec 2004 Location: East Yorkshire, UK. Posts: 3,987	Re: Hacker Mayflower II - PSU Electrolytics. Have you checked the voltage from the rectifier, I would expect it has seen better days. If needed can be replaced with silicon bridge rec + resistor. John.