Black Star 3225MP – Conversion to an illuminated LCD feasible? - UK Vintage Radio Repair and Restoration Discussion Forum

Chris55000 · 18th Oct 2021, 12:58 pm

Hi!

Just a quick one!

I have just received a Black Star 3225MP in the post this morning, it arrived undamaged and the only thing rattling was the spare fuse in the i.e.c. mains inlet. Fuse Drawer!

Apart from the lack of a s.m., (which isn't too serious as these meters are only 7106 based), is it feasible to replace the LCD with a type that can be illuminated?

(I believe you could get an E.L. panel that was designed for these LCDs at one time, are they still available?)

I think the LCD is one of those standard 3½ digit 40–pin direct drive types that's made for the '7106 & it's clones with "low batt" (obviously not needed with the "MP" models!) and "minus" annunciators!

The display as it comes is far too dark and murky for my eyesight!

Chris Williams

Lloyd 1985 · 18th Oct 2021, 1:23 pm

Hi,

I have managed to backlight the LCD in one of my Fluke multimeters before, I used the LED backlight and it’s diffuser from a broken iPod display! First thing to check is whether or not the LCD is suited to backlighting, luckily the Fluke’s display was, check by shining a light through the back of it, some displays aren’t transparent enough, this is caused by the silver backing, another of my Fluke’s was like this, the backing blocked all the light so I didn’t bother with that one. If your feeling brave you can peel off the silver backing and replace it with something more translucent, but it’s a bit of a faff.. You could try lighting it from the side of the LCD, but I have always found that approach unsatisfactory.

Regards
Lloyd

paulsherwin · 18th Oct 2021, 1:38 pm

I have one of these meters, so will be keeping an eye on this thread. I don't find the display particularly difficult to read, but agree it would be better backlit, so I may try this mod myself once you've worked out how to do it

I'd be grateful for any docs you come across too.

Chris55000 · 18th Oct 2021, 1:54 pm

Hi!

Thanks for the tip Lloyd – I can try that no problems!

I can certainly produce a basic circuit diagram for the meter I have got, but one thing I wouldn't be able to reproduce easily is Black Star's parts list with the official part numbers, and to document the differences between the 3210 & the 3225 I'd have to buy a 3210!

Has anyone tried TTi yet? – I don't want to bother Tris Wilding again so soon after he so generously provided the Orion Manual for me!

Chris Williams

18th Oct 2021, 12:58 pm	#1
Chris55000 Nonode Join Date: Aug 2007 Location: Walsall Wood, Aldridge, Walsall, UK. Posts: 2,864	Black Star 3225MP – Conversion to an illuminated LCD feasible? Hi! Just a quick one! I have just received a Black Star 3225MP in the post this morning, it arrived undamaged and the only thing rattling was the spare fuse in the i.e.c. mains inlet. Fuse Drawer! Apart from the lack of a s.m., (which isn't too serious as these meters are only 7106 based), is it feasible to replace the LCD with a type that can be illuminated? (I believe you could get an E.L. panel that was designed for these LCDs at one time, are they still available?) I think the LCD is one of those standard 3½ digit 40–pin direct drive types that's made for the '7106 & it's clones with "low batt" (obviously not needed with the "MP" models!) and "minus" annunciators! The display as it comes is far too dark and murky for my eyesight! Chris Williams __________________ It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!

18th Oct 2021, 1:23 pm	#2
Lloyd 1985 Nonode Join Date: Jun 2008 Location: Coningsby, Lincolnshire, UK. Posts: 2,817	Re: Black Star 3225MP – Conversion to an illuminated LCD feasible? Hi, I have managed to backlight the LCD in one of my Fluke multimeters before, I used the LED backlight and it’s diffuser from a broken iPod display! First thing to check is whether or not the LCD is suited to backlighting, luckily the Fluke’s display was, check by shining a light through the back of it, some displays aren’t transparent enough, this is caused by the silver backing, another of my Fluke’s was like this, the backing blocked all the light so I didn’t bother with that one. If your feeling brave you can peel off the silver backing and replace it with something more translucent, but it’s a bit of a faff.. You could try lighting it from the side of the LCD, but I have always found that approach unsatisfactory. Regards Lloyd

18th Oct 2021, 1:38 pm	#3
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,927	Re: Black Star 3225MP – Conversion to an illuminated LCD feasible? I have one of these meters, so will be keeping an eye on this thread. I don't find the display particularly difficult to read, but agree it would be better backlit, so I may try this mod myself once you've worked out how to do it I'd be grateful for any docs you come across too.

18th Oct 2021, 1:54 pm	#4
Chris55000 Nonode Join Date: Aug 2007 Location: Walsall Wood, Aldridge, Walsall, UK. Posts: 2,864	Re: Black Star 3225MP – Conversion to an illuminated LCD feasible? Hi! Thanks for the tip Lloyd – I can try that no problems! I can certainly produce a basic circuit diagram for the meter I have got, but one thing I wouldn't be able to reproduce easily is Black Star's parts list with the official part numbers, and to document the differences between the 3210 & the 3225 I'd have to buy a 3210! Has anyone tried TTi yet? – I don't want to bother Tris Wilding again so soon after he so generously provided the Orion Manual for me! Chris Williams __________________ It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!