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Products => Test Equipment => Topic started by: daveyk on August 07, 2021, 05:33:46 pm

Title: LED Strips to Replace CFL Tubes in TDS3000 Series scopes
Post by: daveyk on August 07, 2021, 05:33:46 pm
Does anyone have good experience with LED replacement of the CFL Tubes in a Tek TDS3000 series scope?

I work on an instrument that uses the same display.  It is commonplace for the instrument to be dropped and the tubes broken.  The source of the replacement tubes has run dry for the most part, and an LED upgrade would so much nicer, maybe.

Can anyone point me to a driver PCB and LED Strip that is appropriate for these displays?  Without looking, the DFL tubes are about 6" long.  They are dim-able in the instrument in use, but that capability could be eliminated if need be.

There are probably numerous options, but I would prefer experience and not have to engineer a solution from scratch.  At least point me towards parts that should work - lol.

Thanks
Title: Re: LED Strips to Replace CFL Tubes in TDS3000 Series scopes
Post by: daveyk on August 07, 2021, 06:46:35 pm
On my own, I found this:

https://store.lcdparts.net/UB35160LED3220X2MS610UB-for-65%E2%80%9D-Dual-Lamp-LCD-Screen_p_4548.html

With shipping, this is a $170 solution (and I did order one kit).  For what I use it for, that is acceptable, but I would bet a lot cheaper solutions are around.  I just have never used strips of LED lights and do not know how to order to match up with a driver PCB.  Are the LEDs typically all in parallel or series, or a combination of both?

I would like to find a roll of LED strips that can be cut and and wired to and then a driver PCB.
Title: Re: LED Strips to Replace CFL Tubes in TDS3000 Series scopes
Post by: TheDefpom on August 07, 2021, 07:41:48 pm
I picked up some LED strips with drivers (yet to be needed) from Aliexpress a couple of years ago, maybe have a browse around there.
Title: Re: LED Strips to Replace CFL Tubes in TDS3000 Series scopes
Post by: nctnico on August 07, 2021, 08:55:49 pm
On my own, I found this:

https://store.lcdparts.net/UB35160LED3220X2MS610UB-for-65%E2%80%9D-Dual-Lamp-LCD-Screen_p_4548.html (https://store.lcdparts.net/UB35160LED3220X2MS610UB-for-65%E2%80%9D-Dual-Lamp-LCD-Screen_p_4548.html)

With shipping, this is a $170 solution (and I did order one kit).  For what I use it for, that is acceptable, but I would bet a lot cheaper solutions are around.  I just have never used strips of LED lights and do not know how to order to match up with a driver PCB.  Are the LEDs typically all in parallel or series, or a combination of both?

I would like to find a roll of LED strips that can be cut and and wired to and then a driver PCB.
These are horribly expensive!

Buy something like this:
https://www.ebay.com/itm/271944994132 (https://www.ebay.com/itm/271944994132)

But be aware that you'll need to adjust the current sensing resistor if you are cutting LEDs from the strip AND determine how many LEDs are in series; you can't cut an arbitrary number of LEDs! I have used similar strips in (IIRC) two or three TFT screens and they work like a charm.
Title: Re: LED Strips to Replace CFL Tubes in TDS3000 Series scopes
Post by: james_s on August 07, 2021, 10:06:20 pm
About 8 years ago I replaced the backlight in a friend's Toshiba Libretto subnotebook with LED strips. I bought a generic retrofit kit, I think it was about $20 and I had to trim the length of the strips to size but overall it was fairly straightforward. It looked good and as far as I know it's still working.