Been modelling in PSU designer a power supply for an 807 stereo amplifier using a pair of 807s in each channel class AB1 ultralinear.
Im allowing an idle current of 60mA and a max current of 200mA as seen on the screenshots below.
I am aiming for a voltage of 450V, my PT supplies 690V (345-0-345) Im actually beginning to wonder if i might need a slightly higher voltage PT, but overall the models seem to provide enough voltage at low power, you can tweak all the variables all night with this software, but its hard to get the right balance between voltage under full load and when idle or a lower load, lets face it, I guess its nothing to worry about under max power as its not like you run it on full power, but its good to have it provide the most stable voltages across the range.
My main concern was the datasheet for the 866 specifies the primary filter cap at 4uF max, but I find that increasing this value actually helps somewhat.
I get 460V on low load and it drops to about 430V or so under max load.
I can tweak this to provide a lower voltage when idle, but it drops off even more when under load.
Any tweaks anyone could suggest are appreciated, would an RC choke work better with these perhaps?
Idle current:
Max current (im also not entirely sure about the warning message either):
Im allowing an idle current of 60mA and a max current of 200mA as seen on the screenshots below.
I am aiming for a voltage of 450V, my PT supplies 690V (345-0-345) Im actually beginning to wonder if i might need a slightly higher voltage PT, but overall the models seem to provide enough voltage at low power, you can tweak all the variables all night with this software, but its hard to get the right balance between voltage under full load and when idle or a lower load, lets face it, I guess its nothing to worry about under max power as its not like you run it on full power, but its good to have it provide the most stable voltages across the range.
My main concern was the datasheet for the 866 specifies the primary filter cap at 4uF max, but I find that increasing this value actually helps somewhat.
I get 460V on low load and it drops to about 430V or so under max load.
I can tweak this to provide a lower voltage when idle, but it drops off even more when under load.
Any tweaks anyone could suggest are appreciated, would an RC choke work better with these perhaps?
Idle current:
Max current (im also not entirely sure about the warning message either):
i will always follow follow manufacturers' recommendations...
866 rectifier.... https://frank.pocnet.net/sheets/049/8/866A.pdf
if using a choke, you can use bigger caps after the fuse...
Is that a composite power transformer? meaning with filament coils and other windings?
if so, then PSU2 can not see the effects of those on the actual psu...
you loading is the maximum or peak loading in case of AB1, what input power?
your warning message means that you should add some external resistances on the secondary winding
in order to lower that 1A current that was exceeded...
your curves seem to indicate a smooth turn on, with no overshoots, to me they look good..
866 rectifier.... https://frank.pocnet.net/sheets/049/8/866A.pdf
if using a choke, you can use bigger caps after the fuse...
Is that a composite power transformer? meaning with filament coils and other windings?
if so, then PSU2 can not see the effects of those on the actual psu...
you loading is the maximum or peak loading in case of AB1, what input power?
your warning message means that you should add some external resistances on the secondary winding
in order to lower that 1A current that was exceeded...
your curves seem to indicate a smooth turn on, with no overshoots, to me they look good..
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Looking again at the datasheet, I realised that im not actually far out.
This datasheet gives more details regarding configuration.
http://www.r-type.org/pdfs/866a.pdf
It doesnt give any figures for running at 400V, but 20uF would be about right at 400V or so, since the figures are per tube.
It is a composite transformer, and has the heater windings on it.
Power input would be about 90W