Magnum 257HP Talk Back Enable

[BBB]

I ran my 257HP-TB radio last night on the bench. That thing has awesome loud & clear AM modulation. SSB was right on.

I wondered what the "TB" meant in the product name and saw the CB Radio Magazine's video listed below. I learned that the last incarnation of the radio included available Talk Back circuitry where as in the previous models it did not; Hench the product ID as 257HP-TB on the back of the radio.

He mentioned that there is an option to enable it in the radio some how or have it automatically enabled when using the 257 Extreme Echo mic which I have. (The 257 Extreme Echo mic is a factory modified 2018 Extreme echo mic that uses the radio to power the echo mic so no 9V battery is needed)

I noticed that when I plugged an external speaker in the back of the radio, talkback was indeed enabled, yet I could not control the volume of it with the pot described on the back of the mic or disable it as described in the video. The talkback is not present when just the internal speaker is used.

I would prefer that the talkback be disabled when using an external speaker and the 257 Extreme Echo mic. Maybe I'm missing something or need to disable TB in the mic or radio somehow now.

Just asking if anyone else has noticed this non-disabling, non adjustable talk back scenario when using the 257 Extreme Echo mic with the later 257HP-TBs? Thanks.

 

[9C1Driver]

I thought the volume control was one of those tiny pots on the echo mic itself. I'll have to check.

 

[BBB]

It is the lower one. It's interesting that the talk back stays on full blast no matter what the pot is set at when an external speaker is plugged into the 1/8" jack in the back of the radio. I'm almost certain that there is no talkback when no external speaker is plugged in, but I'll double check that.

You would assume turning the pot all the way down (counter clockwise) would effectively turn off the talkback. Maybe the pot needs replaced. That would make sense if there is no level adjustment.

I guess there is a chance that the radio was modified internally to have talkback with the stock mic. That would be weird as I purchased the radio brand new from R&R. I have the unused stock mic, so I'll check the status of talk back with that connected. Thanks.