Ranger base S/RF bar graph meter in frequency display readout.

[SMILEX2692002]

Years ago a guy who used to work on my radios had some way to enable the S/RF bar graph meter
that is embedded in the display read out of a 2990.
Does anyone know how to do that?

If you look at the display board of a 2950 it is already active.
The display board in a 2990 is pretty much the same.
But that S/RF bar graph indicator is not active.

I have a new 2995dxCF now.
I'm wondering if this could be done to this radio?
Same goes for this radio. I can see the bar graph in the frequencies play but it is not active.

 

[sp5it]

Without 2995 schematic would be hard, but...
Check for connector socket CN602 (2pin) on CPU board. That's where s/rf signal goes from mainboard.
Location: http://www.radiomanual.info/schemi/Vari/Ranger_RCI-2950_Secret_book.pdf
Mike

 

[SMILEX2692002]

Possibly a jumper between those two pins would do it?

 

[Handy Andy]

Not a jumper between, Jumper TO
You can get S meter signal from J18...Mainboard jumper...

Do you have a CPU "display board" that looks like this?

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CN602 is the ONLY set of pins that ARE NOT CONNECTED to anything.

CN602 header, Pin 2 is S/RF - but you can get that off of J18 on Main board - CENTER PIN is SIGNAL

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You can test Ground on CPU - to CN602, to find it's ground pin. LEAVE THAT OPEN - PIN is or should be - if your board is oriented like in the photo above, below PIN2

So the PIN TWO ON CN602 - that you send signal FROM CENTER OF J18 to - MAKE SURE IT IS NOT to the GROUND PIN...DO NOT TIE SIGNAL TO GROUND PIN...

Use Top Pin of CN602 - the board uses common grounding thru CPU connector for PLL as all other signal - so simple stuff - just use a jumper...

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Just not sure if it's strong enough to drive both Analog Meter as well as On Board LCD one...

 

[SMILEX2692002]

I think I have the same board. Doesn't seem to hard.

 

[Tweek]

I tried driving a voltage in to the pin on the lcd display, but no bar graph. Trying to see if something on the display needs to be enabled...

Dave

 

[Handy Andy]

I tried driving a voltage in to the pin on the lcd display, but no bar graph. Trying to see if something on the display needs to be enabled...

Dave

Are you trying to Drive both Meter and S/RF LCD display at the same time?

Careful with this, watch for weighting effects.

• Weighting; Referring to the level of signal and the amount of signal needed to drive the display, it's scalar and works with an amp inside the CPU which then "polls"(Those LCD segments that show a "outline" or highlight), that means the CPU is sending data to the LCD display from the CPU itself. the circuit internally though, may not be setup to use that signal like their earlier cousins.
• The effort is to try it, if it don't work then the support circuitry isn't even there to utilize it.
• IT would use a cap and couple of resistors to provide feedback gain (Linear operation for LOG scaling) R628 and others inclusive to make the reading work.

Best to remove the jumper pin, and actually measure from Pin 1 to 2 on the connector - if a "trickle voltage" appears, this means the pin jumper may not work, the CPU has biased the pin for another purpose which you cannot control. IF there is no voltage, check to see if you have a resistive reading from 1 to 2 - if it's below 10K then you have something there, you'll have to look further