I tried just replacing the +18db amp with the HDA-20, hoping the extra amplification would be a simple fix. But when I put it in, I seem to get no signal through it at all. Questions ...
- is my underlying assumption correct .. am I making a like-for-like swap with simply more gain?
- there seems to be a little green hole near the power-in that i would guess could be a power indicator. However, there is no light there ... should there be? It is indeed plugged into a working power strip with coax connecting the transformer to the unit, to take care of the obvious
- what does the adjustable gain do, and how do I know what is low or high, min or max? it just seems to spin without any stopping point
Can you help me?
Thanks.

