PRO-2023 Tap problem

[lest69]

In the past, I successfully tapped a PRO-90, which is still working. I recently bought a PRO-2023. I was able to tap the discriminator pin (10). However, when I plug in the cable to connect to the PC, the audio level coming from the speaker drops significantly, and the signal received in the PC is very low. I also lose control of squelch when the cable is in place. It works completely fine when I disconnect the cable. In comparing the ICs of the PRO-90 and 2023, the typical output voltage from the discriminator should be about 5x greater in the 2023 than in the 90, yet it is actually less. Does anyone know why the drop in voltage, or how I can correct it?
Thanks
Andrew (lest69)

 

[Al42]

The 2023 probably has a higher source impedance, so you're loading it down more. Try a 10k resistor in series with your tap.

 

[lest69]

10k resistor

Actually, I tried it with and without a 10k resistor. There was no change between the two cases.