Hacker Mayflower tuning problem - Page 3 - UK Vintage Radio Repair and Restoration Discussion Forum

majoconz · 26th Apr 2021, 12:36 am

The 'blob' just above my yellow square - as you say, may be a blob of solder discoloured a bit.

Pilot Mariner · 3rd Oct 2021, 4:10 pm

An update on this, and due to more pressing jobs through the summer months I have eventually managed to get back to finishing this Hacker Mayflower. Apologies for the abrupt ending of my last post leaving the thread hanging for a few months.

A quick recap, members may remember that this HM2 was tuning normally down to approx 90MHz where the local Cannock Chase radio station is, and not tuning further down to Radio 2 even though the pointer and tuner mechanism still had an inch or so of travel left.
The eventual cure was to bravely venture inside the gorler tuner unit add a few pfs across one of the permeability tuning coils/trimmer capacitor.

The first picture shows two small disc capacitors that I used (circled) in series in order to get the correct capacitance across the coil/trimmer.
This now brings in Radio 2 loud and clear at 88.3MHz and other stations at their correct place on the scale after a slight tweak to the pointer position on the cord.

In addition, whilst I had the chassis out in order to do the usual service I decided to try out Stevehertz's tone modification. Steve's post is here:-

https://www.vintage-radio.net/forum/...ight=mayflower

This really made an improvement to the sound giving a nice punchy bass. I therefore decided to make this arrangement permanent as it seemed easy to incorporate as shown in the 2nd picture, with the additional components circled.

The link connecting the tape O/P and gram I/P is removed and replaced by the 270K resistor ensuring that the green wire carrying the audio from the front end is connected to the tape out socket and the coax feed up to the volume control is connected to the gram I/P ie each end of the 270K resistor. Note that doing the mod this way causes it to be out of circuit if the gram input is ever used, which does not really bother me

An unused tag is available to connect the 100K resistor and the 6.8nf capacitor neatly together, and a nearby earth tag is available for the capacitor.

I have also restored the rather tatty cabinet shown.

stevehertz · 3rd Oct 2021, 6:38 pm

Nice work Mark.

Pilot Mariner · 3rd Oct 2021, 7:43 pm

Thanks Steve and thanks to all who helped.

Mr 1936 · 4th Oct 2021, 8:15 am

Hi

Thanks for the recap on the re-cap !

It's always nice to hear the "end of the story", especially when it's a positive outcome.

26th Apr 2021, 12:36 am	#41
majoconz Heptode Join Date: Jan 2008 Location: Ashhurst, Manawatu, New Zealand Posts: 571	Re: Hacker Mayflower tuning problem The 'blob' just above my yellow square - as you say, may be a blob of solder discoloured a bit. Attached Thumbnails __________________ Cheers - Martin ZL2MC

3rd Oct 2021, 4:10 pm	#42
Pilot Mariner Hexode Join Date: Jun 2003 Location: Burntwood, Staffordshire, UK or Kabaty in Warsaw Poland. Posts: 439	Re: Hacker Mayflower tuning problem An update on this, and due to more pressing jobs through the summer months I have eventually managed to get back to finishing this Hacker Mayflower. Apologies for the abrupt ending of my last post leaving the thread hanging for a few months. A quick recap, members may remember that this HM2 was tuning normally down to approx 90MHz where the local Cannock Chase radio station is, and not tuning further down to Radio 2 even though the pointer and tuner mechanism still had an inch or so of travel left. The eventual cure was to bravely venture inside the gorler tuner unit add a few pfs across one of the permeability tuning coils/trimmer capacitor. The first picture shows two small disc capacitors that I used (circled) in series in order to get the correct capacitance across the coil/trimmer. This now brings in Radio 2 loud and clear at 88.3MHz and other stations at their correct place on the scale after a slight tweak to the pointer position on the cord. In addition, whilst I had the chassis out in order to do the usual service I decided to try out Stevehertz's tone modification. Steve's post is here:- https://www.vintage-radio.net/forum/...ight=mayflower This really made an improvement to the sound giving a nice punchy bass. I therefore decided to make this arrangement permanent as it seemed easy to incorporate as shown in the 2nd picture, with the additional components circled. The link connecting the tape O/P and gram I/P is removed and replaced by the 270K resistor ensuring that the green wire carrying the audio from the front end is connected to the tape out socket and the coax feed up to the volume control is connected to the gram I/P ie each end of the 270K resistor. Note that doing the mod this way causes it to be out of circuit if the gram input is ever used, which does not really bother me An unused tag is available to connect the 100K resistor and the 6.8nf capacitor neatly together, and a nearby earth tag is available for the capacitor. I have also restored the rather tatty cabinet shown. Attached Thumbnails

3rd Oct 2021, 6:38 pm	#43
stevehertz Dekatron Join Date: Sep 2011 Location: Rugeley, Staffordshire, UK. Posts: 8,831	Re: Hacker Mayflower tuning problem Nice work Mark. __________________ A digital radio is the latest thing, but a vintage wireless is forever..

3rd Oct 2021, 7:43 pm	#44
Pilot Mariner Hexode Join Date: Jun 2003 Location: Burntwood, Staffordshire, UK or Kabaty in Warsaw Poland. Posts: 439	Re: Hacker Mayflower tuning problem Thanks Steve and thanks to all who helped.

4th Oct 2021, 8:15 am	#45
Mr 1936 Heptode Join Date: Mar 2017 Location: Romsey, Hampshire, UK. Posts: 521	Re: Hacker Mayflower tuning problem Hi Thanks for the recap on the re-cap ! It's always nice to hear the "end of the story", especially when it's a positive outcome.