Has anyone tried these LED replacements for the large meters used in RT-707, etc?

[saabracer23]

I rebuilt a SX 1280 for a friend and he wanted warm white LEDs installed. He wanted the same look for his RT-707 and CT-F1000 and asked about LEDs for the meter lights. I did see that there were LED replacements. The original lamp is an 8v 55mA Axial lamp. I asked David (Dgwojo) about it and he sent me a bag of his finest rectified boards.


From what I understand these were made specifically for this purpose. I installed the first one and the board is all the way up to the meter assembly, it is literally touching.


The problem is that I cannot get the meter cover to seat back down. Normally it’ll just snap back together, but there’s an interference and it will not go all the way together.


I am curious if anyone has used these and if they have any tips, the only thing I can think of would be to turn the board so that it is angled, and the LEDs are facing more downward to the meter face. my concern is with LEDs being so directional it wouldn’t look good. so I thought I would just see if anyone here has already tackled this problem, thank you so much.

Dan

 

[Ray66]

Asside from the re-assembly issue I suspect you will not be happy with the non-uniform light distribution you will get on the meter face. I used some of those recently on a Technics SA-303 receiver. There were 10 of them lined up along the plastic dial face diffuser. You can see the spots from each LED as they enter the diffuser, however in this case the light is uniform by the time it gets to the front of the unit.

 

[mcgjohn]

I rebuilt a SX 1280 for a friend and he wanted warm white LEDs installed. He wanted the same look for his RT-707 and CT-F1000 and asked about LEDs for the meter lights. I did see that there were LED replacements. The original lamp is an 8v 55mA Axial lamp. I asked David (Dgwojo) about it and he sent me a bag of his finest rectified boards.
View attachment 3224539

From what I understand these were made specifically for this purpose. I installed the first one and the board is all the way up to the meter assembly, it is literally touching.
View attachment 3224540

The problem is that I cannot get the meter cover to seat back down. Normally it’ll just snap back together, but there’s an interference and it will not go all the way together.
View attachment 3224541

I am curious if anyone has used these and if they have any tips, the only thing I can think of would be to turn the board so that it is angled, and the LEDs are facing more downward to the meter face. my concern is with LEDs being so directional it wouldn’t look good. so I thought I would just see if anyone here has already tackled this problem, thank you so much.

Dan

not easy to fit in place. And if you don't lower the voltage with an in line resistor they will likely be too bright.

 

[Ray66]

Yes, brightness will be the other issue. The axial lamps in the Technics SA-303 are spec'd at 8VAC 80mA. As you can see in the attached comparison image the LED appears to be brighter. I didn't measure the current draw directly but the online spec said it would be ~10mA. The receiver was perhaps a bit brighter than I wanted but it doesn't matter where I'm currently using it. As @mcgjohn mentioned, a resistor to limit the current could be used to cut the brightness.

 

[Bruno Primas]

One trick is to leave the burned-out bulb in and mount the new axial led if there is room. The led light has to shine through the old bulb and it diffuses the brightness down.