Lazarus! Arise from your back burner.
A few years ago I posted a project that shrinks the 9/16-inch digits on the SanJian PLJ6-LED frequency display so it fits behind the dial window of a Siltronix 80/90 VFO or the VFO window of a Tram D201.
And then reality set in. Removing the big digits from the PLJ circuit board was hard on the extra-thin foil pads as it turned out. Had a yield of working displays under fifty percent. Not good. Had one go bad in the customer's radio after it went home, digits went dark. Wasn't a big deal to make good and swap out his display. Just the same this made it look like a support nightmare in the making. Enthusiasm waned and it fell onto that proverbial back burner for years. Sold a few that we installed here, but that was it. No way I'll offer it on fleabay if it's a failure risk. Don't need the headaches.
Had a few folks ask about this item, and then I spotted white 3-digit sticks this size. Bought a small batch of this pc board and had similar issues with some of them failing when assembled. This is the kind of foil-trace damage that caused the issues.
Turns out that just clipping the leads from the old digits is easier on the pc board. Removing the clipped-off leads one-by-one only requires touching the iron tip to a lead and pulling it out.
Now sucking the solder from a hole with no component lead, only solder is easier on the foil traces. But not easy enough. Still had foil damage and failure issues using the Hakko 300.
Then my idiot light came on. I hold the board with the clipped-off lead wires a couple inches above the bench surface. The iron tip goes against one protruding lead until the solder melts and the lead leans sideways. I rap the board against the bench surface and the lead, solder and all splatter onto the bench. Leaves and empty hole in the board with a minimum of heat stress. The threaded pillars on all four corners take the impact safely.
The Hakko 300 with the hollow tip and vacuum pump is an excellent tool for many rework jobs. Just not this one.
The white digits are so bright I have to turn down the camera's exposure index way, way down.
So far I've modded six this way with only one failure. That one refuses to light up at all. Totally dark. The one mistake I can point to is not hooking it up to test before clipping the old digits. Could have been DOA out of the package. Now I'll never know. And I won't mod another PLJ board without checking it first.
Got some more 0.36-inch digits coming soon. Who knows, maybe this will turn into a marketable item, if it proves more reliable than the first attempt was.
73
A few years ago I posted a project that shrinks the 9/16-inch digits on the SanJian PLJ6-LED frequency display so it fits behind the dial window of a Siltronix 80/90 VFO or the VFO window of a Tram D201.
And then reality set in. Removing the big digits from the PLJ circuit board was hard on the extra-thin foil pads as it turned out. Had a yield of working displays under fifty percent. Not good. Had one go bad in the customer's radio after it went home, digits went dark. Wasn't a big deal to make good and swap out his display. Just the same this made it look like a support nightmare in the making. Enthusiasm waned and it fell onto that proverbial back burner for years. Sold a few that we installed here, but that was it. No way I'll offer it on fleabay if it's a failure risk. Don't need the headaches.
Had a few folks ask about this item, and then I spotted white 3-digit sticks this size. Bought a small batch of this pc board and had similar issues with some of them failing when assembled. This is the kind of foil-trace damage that caused the issues.
Turns out that just clipping the leads from the old digits is easier on the pc board. Removing the clipped-off leads one-by-one only requires touching the iron tip to a lead and pulling it out.
Now sucking the solder from a hole with no component lead, only solder is easier on the foil traces. But not easy enough. Still had foil damage and failure issues using the Hakko 300.
Then my idiot light came on. I hold the board with the clipped-off lead wires a couple inches above the bench surface. The iron tip goes against one protruding lead until the solder melts and the lead leans sideways. I rap the board against the bench surface and the lead, solder and all splatter onto the bench. Leaves and empty hole in the board with a minimum of heat stress. The threaded pillars on all four corners take the impact safely.
The Hakko 300 with the hollow tip and vacuum pump is an excellent tool for many rework jobs. Just not this one.
The white digits are so bright I have to turn down the camera's exposure index way, way down.
So far I've modded six this way with only one failure. That one refuses to light up at all. Totally dark. The one mistake I can point to is not hooking it up to test before clipping the old digits. Could have been DOA out of the package. Now I'll never know. And I won't mod another PLJ board without checking it first.
Got some more 0.36-inch digits coming soon. Who knows, maybe this will turn into a marketable item, if it proves more reliable than the first attempt was.
73
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