Re: [help] Only noise being seen while IQ balance / phase lo / phase hi.

Don VE3IDS
 

Jose
Let's start somewhere. IC 10 pin 5 is an input with a simple voltage divider to set the level. It should be about 4.21 and you are much lower? With power off, check the resistance of each of the 10k resistors, R39&40. Also you could check the voltage of the 12 volt side of R40, the junction of R39&40 and the ground side of R39. This is with your meter negative lead on power supply negative. We want to see if the supply lines are good to that area as well as determining if the resistors are correct. If you need to check the resistor out of circuit, I would suggest rather than trying to unsolder the resistor, clip the lead at the top with a tiny set of cutters so you can solder it back together afterwards. 
Did you use an ohmmeter to identify the resistors or did you go by the color bands?

73 Don ve3ids

On Thu., May 28, 2020, 1:29 p.m. Jose Tent, <ksaito2@...> wrote:
AW daing it. Copied over the typo again.   Yes.   i meant pin 5 and 6.... not pin 4,5.

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