Competition Electronics 538002-SSI ProChrono Digital Chronograph
(Originally purchased Nov 2018 through Amazon)
When I first set up my chronograph in 2018 I thought it was broken. Learned it was my fluorescent shop lights AND the first LED utility light I tried that were "pulsing" right in the critical frequency range which caused massive read errors. I solved the problem by using a 500W incandescent (NO pulsing) utility light that has worked flawlessly the last 3+ years... until the bulb burned out! I could have just replaced that bulb but I really wanted something more efficient that was less of a 500 deg F fire hazard. I found some USB (5V) LED strip lights on Amazon for $7 and ordered two 16' strips. I also ordered a set of 120Vac-5Vdc USB charger blocks for $3/block. Total cost for this back-light project was $20 in parts and about an hour of my time to assemble it.
Nothing fancy here. Cut some strips of white boxboard (Little Debbie treat addiction resurrected from my distant childhood;-) about the same size as the shades to mount the LED strips. Cut and taped the LED strips to the boxboard and wired (soldering required) the cut sections back together. Tested the connections then (electrical) taped the new LED arrays to the shades. Initially tested the new LED lights with a recently acquired Crosman Shockwave 177 and got the SAME readings from my testing a week before the incandescent back-light burned out. So far the new LED lights are running MUCH cooler (barely warm to the touch) and I've had no missed or error readings.
Next upgrade will be to wire in a 9Vdc power brick so I can stop buying 9V batteries. My chronograph needs are never mobile so wired back-lights and power is fine.
One additional benefit from the upgrade is that my target stays well illuminated by the LEDs. The prior setup with the incandescent lamp sometimes cast a shadow on the target.
Photos of the upgrade...
Chronograph reading from my Winchester 1100s and 7.9 grain CPHP at 966 fps MV.
USB LED cables plugged into the USB power blocks.
One shade with the new LED back-lighting.
Old setup worked well, my review linked here...
https://www.amazon.com/gp/customer-reviews/R3AFT0BH612PSD