mybud
Well-known member
I thought of building a negative ground Rangefinder for fun, since I have a supply of 2N1304s.
So what I did was...
Reverse C3 (47uF), bridge lugs 1 and 8 on the TC1044 sockets (measures 9V), leave the 5817 diode in place as per the schematic. I also tried connecting pin 3 to the trimmer (to solve a missing ground connection?) but no luck. Now disconnected.
On first fire there is a very faint hint of signal, which doesn't change if I fiddle with the bias trimmer (changed this to 100k and mounted topside after removing the original 5k). The LED (not shown here) works, indicating that the power connections work (at least as far as the LED's concerned).
What's troubling is that neither the trimmer nor the 1304 show anything other than 0V. What appears to be happening is that there is no power reaching the 1304 from the 5817 on. Probably a simple solution but I can't seem to find it, even after checking other related forum posts.
Any help gratefully received (and wishing all our US friends the best for the 4th of July).
So what I did was...
Reverse C3 (47uF), bridge lugs 1 and 8 on the TC1044 sockets (measures 9V), leave the 5817 diode in place as per the schematic. I also tried connecting pin 3 to the trimmer (to solve a missing ground connection?) but no luck. Now disconnected.
On first fire there is a very faint hint of signal, which doesn't change if I fiddle with the bias trimmer (changed this to 100k and mounted topside after removing the original 5k). The LED (not shown here) works, indicating that the power connections work (at least as far as the LED's concerned).
What's troubling is that neither the trimmer nor the 1304 show anything other than 0V. What appears to be happening is that there is no power reaching the 1304 from the 5817 on. Probably a simple solution but I can't seem to find it, even after checking other related forum posts.
Any help gratefully received (and wishing all our US friends the best for the 4th of July).
