But seeing as how new signups have been disabled there for some time, it made sense to repost it here. Made the customer happy, and that's the objective, after all.ġ6:49:17 GMT -5 2600 said:I posted this on the CB Tricks forum. The buffer is a simple solution to the mismatch between the counter's input-drive requirements and the LO-circuit power that we can "borrow" to drive its input without reducing the radio's performance. No way to correct for the carrier-frequency change in USB. Of course it only reads correctly in AM mode. Not pretty, but solid enough for a base station. Really should have selected aperture priority to get some depth-of-field and used the tripod to make this clearer, but this is how it's built in this radio. CBST-23 (Sidetalk 23) DX2300B P2300 Pace-Mate 2 W/5812. The output voltage to the counter is only a little less than the input, but has more than enough drive current for the input of the counter. The circuit's input impedance is pretty high, so the radio's LO output level is not loaded down. The size of this cap is not critical, and there's probably a LOT of leeway to the values that will work.Īll it really provides is an impedance step down. Won't reduce the LO drive voltage to the radio's mixer circuits. The disc capacitor feeding the gate of the JFET is 8.2pf. It does not provide any voltage gain, only current gain. Rather than diddle with the counter's input circuit, I added a JFET buffer amp. The input-side terminal is soldered right to the radio's large filter capacitor, so it won't need one added to its input pin. They will sometimes oscillate and cause headaches without this capacitor. The 10uf electrolytic on the output is to keep the regulator stable.
The board foil it's soldered to provides plenty of heat sinking, and simplifies getting it mounted. The TO-220 part is overkill, but about the same price as the small version. The tiny TO-92 version of this regulator is not quite big enough to power this display. The 7808T regulator we used here is soldered directly to the ground foil on this radio. But most radios won't have that extra capacity. If the radio's built-in 8-Volt regulator can supply the extra current to run one of these, that's fine. 9 Volts is okay, but 8 Volts seems to be the sweet spot. The higher the power-supply voltage, the more heat it throws.
PACE SIDETALK 1000B MODS PC
This is because of the 5-Volt SMT regulator on the display's pc board. The other limitation of these otherwise-fine displays has to do with the display's supply voltage. If you see that, you can be fairly confident your transmit power will also be reduced. You'll know this happens when touching the counter's input wire to the radio causes the receiver's signal level to drop. Hooking it directly to the output of a radio's synthesizer tends to load down the local-oscillator (LO) signal. Cut a piece of smoked plex to improve the contrast of the too-bright digits and hide the counter's works, at least a little.įirst problem you may have encountered with these displays is the input sensitivity and low input impedance. The SanJian 6-digit LED counter/display just barely fits in the 3-inch wide window. The extra channels in this radio were a pain in the neck without one, he said. But it had a mechanical clock and the customer wanted a counter display in that window. Any help would be greatly appreciated.I posted this on the CB Tricks forum. Digital frequency display for a really old Pace 1000B 0:28:21 GMT -5 Sandbagger and BBB like this. The only rub is that the "S" meter reading is very "stingy" on AM.
Might there be a component that could be bad in the meter circuit on AM that I am overlooking? I love using this old radio, it's a nice clean vintage unit, and it talks quite nicely. Holding anything up to your face sideways and talking into it. Mimicing the use of a Nokia N-Gage as a cell phone. Using a Nokia N-Gage as a cell phone, thus appearing to hold a sideways taco to ones face.
PACE SIDETALK 1000B MODS ARCHIVE
I did a receive alignment, but didn't really change anything for the meter movement on AM. sidetalk Blog Archive 2007 (1) November (1) Becoming a Father About Me. On SSB, the meter reads as it should, with audio clear and loud. The receive audio is great, clear and loud. The trouble is that on AM, when receiving a strong close range signal, the meter shows only about 3-4 "S" units. I didn't really see any board number anywhere on it, but if I can locate a board number, I'll post it here on this thread. I cleaned it up, did a tuneup on it, and lined up all the crystals so they are on frequency, for the most part (this radio goes up to 27.605). I recently acquired an old Pace Sidetalk 1000B 23 channel AM/SSB base from a friend.
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