But the
>connection point on the circuit board for cold was one point, so the
>cold is in common between the two channels. I did not connect the
>shielding of the cable to the ground.
Instead of connecting the cold wires to handle ground, put a 10 mfd in
series with a 200 Ohms resistor on each wire, and then to ground. Then your
HHB will see 200 Ohms impedance both on pin 2 and 3.
If the shield should be connected to "handle ground" or "HHB ground" is
unclear. It's probably the same. The most common with a high-output mic is
that you connect on both sides.
In order to avoid hum, one must also investigate the option to connect pin 1
of the XLR to the chassis ground pin of the XLR. Sometimes this makes a big
difference, but mostly none at all.
The basic reason why you have a risk for hum with a Telinga (when mains
connected) is that I have saved weight and price on not having enough
shielding of the handle PC board. As you say, it works just fine when you
use it as intended - outside on battery equipment.
Klas.
Telinga Microphones, Botarbo,
S-748 96 Tobo, Sweden.
Phone & fax int + 295 310 01
email:
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