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RCI 2995DX issue
- Thread starter Crambone
- Start date
Without the proper equipment to properly align the frequency I wouldn't tinker with usb,lsb frequencies. Sounds like it needs a proper alignment
Do you have any way to set the 10.6975 crystal for each mode?
A fairly-new ham radio that's been calibrated to WWV can be used to "sniff" those frequencies inside the radio. A coax jumper with the shell threaded back over the plug will expose the center pin, This makes it into a half-inch long "sniffing" antenna when you connect it to the 'sniffer' radio's antenna socket.
That crystal in the radio has three slug-tuned trimmer coils in it, one for each mode AM, USB and LSB.
Takes a tool with a tiny tip that is NOT made of metal. A normal steel screwdriver tip will disrupt the setting. Has magnetic properties that change the behavior of the coil when it's inserted in the hole. The ceramic-tip and plastic-tip alignment tools are the only way to get those three adjustments straight.
I don't recommend using a frequency counter unless it's known to be accurate, calibrated recently. Also, tapping into the radio's internal signal to measure it can throw off the adjustment when you clip the counter's input probe to the circuit.
Just no good shade-tree way to do this without tools of some kind.
73
A fairly-new ham radio that's been calibrated to WWV can be used to "sniff" those frequencies inside the radio. A coax jumper with the shell threaded back over the plug will expose the center pin, This makes it into a half-inch long "sniffing" antenna when you connect it to the 'sniffer' radio's antenna socket.
That crystal in the radio has three slug-tuned trimmer coils in it, one for each mode AM, USB and LSB.
Takes a tool with a tiny tip that is NOT made of metal. A normal steel screwdriver tip will disrupt the setting. Has magnetic properties that change the behavior of the coil when it's inserted in the hole. The ceramic-tip and plastic-tip alignment tools are the only way to get those three adjustments straight.
I don't recommend using a frequency counter unless it's known to be accurate, calibrated recently. Also, tapping into the radio's internal signal to measure it can throw off the adjustment when you clip the counter's input probe to the circuit.
Just no good shade-tree way to do this without tools of some kind.
73
I have a Rigol DS1054 scope, Sencore FC-71 freq counter, HP 8657A signal gen, HP 8590A Spec AnalyzerFluke 867 meter, and Heathkit VTVM IM13. Im just new to using them but learning thanks to Y'all.
I checked all the PLL Alignment steps up to the OSC upper and lower I cant get a good reading on either. The AM is set to 10.6950 but I cant seem to get the LSB or USB to read. I have radio on 28.000MHz, Mike Gain full counter clock and rf power full clock.
I did not get back to it yet I moved and it’s still in storage till I finish my basement tut and redo. I am at the start framing part of my new work shop so hopefully in the next few months.
You have to ground Test Point 6 (TP6) while keying the radio to get frequency readout on USB and LSB.
TP6 is a small dot of solder just above L18 .......
Works just fine ......
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