Use 1k2/2W instead 2k2/2W from MV to 15V zeners, and you can use 2R load with this rail.
Regards
If you refer to the resistor at 3.3K /1 W in post #116, that sounds ok, only for setting the correct bias current into the zener. Otherwise please tell me whis is the last/correct schematic.
Anyway, thanks a lot !
Your schematic is GREAT and I am going to use the output stage connected to something like a LME49810 as a VAS to make a sturdy rugged PA!
effebi
If you refer to the resistor at 3.3K /1 W in post #116, that sounds ok, only for setting the correct bias current into the zener. Otherwise please tell me whis is the last/correct schematic.
Anyway, thanks a lot !
Your schematic is GREAT and I am going to use the output stage connected to something like a LME49810 as a VAS to make a sturdy rugged PA!
effebi
You can use separate +/-15V PSU (from protect board) and drop out resistors and zeners, in that case no need to set bias current for zeners with different rail voltages.
Rail voltage drop with useing serial bulb in primary is normal if current rise.
Regards
hi apex
even without a bulb.directly connected to ac mains.
ravs
be a vegeterian.....
For high voltage drop there must be high resistance in the circuit. Test your PSU without amp.
pls give me a layout of H900.. please
SEnd to my email.. dj_rh0meo@yahoo.com thank you..
SEnd to my email.. dj_rh0meo@yahoo.com thank you..
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What is power of 2x18 vac transformer, what is voltage on 1000uF/35V cap?
Apex-
Very nice of you to support so many builders!
The PSU has the voltages calculated wrong. before any other diodes and parts, the AC/DC will only BR to 112 and 56 - not 120 and 60...
BR = AC X 1.4 at 100% efficiency not X 1.5....
Silver,
A transformer does not give out a fixed voltage.
The secondary Vac depends on the mains supply voltage (primary Vac) and on the load current Iac.
The DC voltage from the PSU is not a fixed value, it wanders all over the place.
We can measure the worst case highest zero current PSU voltage. We and you will now know what the highest DC voltage you can ever get from the PSU.
Work down from that highest to find typical DC voltages.
hi apex,
i tried your darlington topology.and guess what everything was ok no abnormal
readings.no sagging of voltages. dc offset of 2mv.same reading on every collector.
then i switched back to normal driver stage with mje15032/33 .switched on
2.1mv dc offset.no voltage sagging everything normal.then i saw i forget to add
22ohm resistor which was connected to both emmiters of mje15032/33.as i
connect then every thing messes up.30 mv dc offset.voltages sags 60 to 38
and-60 to-14.different reading on every collector.what should i do.
thanks
ravs
be a vegeterian.....
i tried your darlington topology.and guess what everything was ok no abnormal
readings.no sagging of voltages. dc offset of 2mv.same reading on every collector.
then i switched back to normal driver stage with mje15032/33 .switched on
2.1mv dc offset.no voltage sagging everything normal.then i saw i forget to add
22ohm resistor which was connected to both emmiters of mje15032/33.as i
connect then every thing messes up.30 mv dc offset.voltages sags 60 to 38
and-60 to-14.different reading on every collector.what should i do.
thanks
ravs
be a vegeterian.....
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