it's great to see that they have included the current specs in the bias setting procedure for this radio.
i don't remember them doing that in other mosfet galaxys, but i could be wrong.
i do want to point out that the way they worded it can cause a bit of confusion.
it might seem like they are saying to first adjust the driver for 50mA and then re-adjust it for 4 volts DC on the gate, but that is NOT the way to do it.
what they want you to do is to be monitoring both the voltage on the gate and the quiescent current at the same time, making sure both end up close to specs.
there comes a point in the bias adjustment where the current starts climbing super fast, and if you're not monitoring it, you won't know it's happening.
so, set the driver bias for 50mA, while watching the DC voltmeter, and if you need to nudge the adjustment up to get to the 4 volts, make sure the current doesn't shoot up when you do it.
for me, i set them at 50mA and check the DC voltage, and if it's anywhere from say 3.2 to 3.8 volts, then i call it good.
the same goes for the finals, with one additional note.
because it's a dual final radio, it's more important that both finals have the same amount of current going to them then having the exact same voltages on the gate IMO.
if someone thinks differently on that, i would be happy to learn why.
LC
i don't remember them doing that in other mosfet galaxys, but i could be wrong.
i do want to point out that the way they worded it can cause a bit of confusion.
it might seem like they are saying to first adjust the driver for 50mA and then re-adjust it for 4 volts DC on the gate, but that is NOT the way to do it.
what they want you to do is to be monitoring both the voltage on the gate and the quiescent current at the same time, making sure both end up close to specs.
there comes a point in the bias adjustment where the current starts climbing super fast, and if you're not monitoring it, you won't know it's happening.
so, set the driver bias for 50mA, while watching the DC voltmeter, and if you need to nudge the adjustment up to get to the 4 volts, make sure the current doesn't shoot up when you do it.
for me, i set them at 50mA and check the DC voltage, and if it's anywhere from say 3.2 to 3.8 volts, then i call it good.
the same goes for the finals, with one additional note.
because it's a dual final radio, it's more important that both finals have the same amount of current going to them then having the exact same voltages on the gate IMO.
if someone thinks differently on that, i would be happy to learn why.
LC
