A little update on the PSU.
I have been using it for some time now and it operates very well, no sign of any noise on the output, well not any that interferes with what it is currently running.
I finally found that a 47 ohm resistor in series with the black wire to the fan reduced the mechanical noise from a hurricane to a purr, much nicer now.
The good news is with a little tweaking of the antenna, low pass filter, new connecting cables and a tweak of the transceiver, I have now got the little linear amp up to over 80 watts output. It is rated at 70max so I have also taped a small 12v fan to it to cool it down when it gets a lot of use. I am very pleased with the power output of the linear, and it makes the need to increase the voltage to 14 volts less urgent, as I dont think the RF power transistor would take it anyway at this power level. The power is confirmed on my MFJ antenna matcher, (switched to through) and also on the meter I fitted to the new PSU. Which shows there are very little in the way of losses in the linear amp.
I have fitted some (very poor quality) 4mm binding posts and a couple of expensive good quality German ones for high current loads.
It would still be nice to be able to vary the voltage but not so essential now. I have left a space on the left of the front panel for a pot should I need to fit one in the future, pending Mark being able to suss it out.
The red LED is a reminder that the supply is connected to the mains (standby supply) and the green one shows its on but it is a little superfluous as the backlight on the meter is enough.
Mike
I have been using it for some time now and it operates very well, no sign of any noise on the output, well not any that interferes with what it is currently running.
I finally found that a 47 ohm resistor in series with the black wire to the fan reduced the mechanical noise from a hurricane to a purr, much nicer now.
The good news is with a little tweaking of the antenna, low pass filter, new connecting cables and a tweak of the transceiver, I have now got the little linear amp up to over 80 watts output. It is rated at 70max so I have also taped a small 12v fan to it to cool it down when it gets a lot of use. I am very pleased with the power output of the linear, and it makes the need to increase the voltage to 14 volts less urgent, as I dont think the RF power transistor would take it anyway at this power level. The power is confirmed on my MFJ antenna matcher, (switched to through) and also on the meter I fitted to the new PSU. Which shows there are very little in the way of losses in the linear amp.
I have fitted some (very poor quality) 4mm binding posts and a couple of expensive good quality German ones for high current loads.
It would still be nice to be able to vary the voltage but not so essential now. I have left a space on the left of the front panel for a pot should I need to fit one in the future, pending Mark being able to suss it out.
The red LED is a reminder that the supply is connected to the mains (standby supply) and the green one shows its on but it is a little superfluous as the backlight on the meter is enough.
Mike
