I have a question on this supply. On the schematic drawn by 621 electronics there a 18v 1w zener on pin 13 on the Lm723. My ps does not have this. Anybody know why
this added what it is for ? Also C5 is a 470uf electrlytic, mine has a small value disc. Why was this changed ? e-mail direct wa9eeh@yahoo.com.
Tenna phase III ps-20 power supply
Re: Tenna phase III ps-20 power supply
In the vintage about 1990 to 1996 handbooks there is the complete build for a 28 volt powersupply.
With good explaination of its workings.
I have built it as a 13.8 supply several times.. Its circuit applys equally to 13 volt setup.
by drawing the circuit of yours 'as is' and 'as shown' in you schematic, then you should be able to
reason out why the difference....and what ehose componenets do, per the handbook version.
With good explaination of its workings.
I have built it as a 13.8 supply several times.. Its circuit applys equally to 13 volt setup.
by drawing the circuit of yours 'as is' and 'as shown' in you schematic, then you should be able to
reason out why the difference....and what ehose componenets do, per the handbook version.
Re: Tenna phase III ps-20 power supply
I have check every circuit I could find and did not find a 18v zener on pin 13 of the LM723 regulator. The capacitor change might be to delay the current limit.k9yli wrote:In the vintage about 1990 to 1996 handbooks there is the complete build for a 28 volt powersupply.
With good explaination of its workings.
I have built it as a 13.8 supply several times.. Its circuit applys equally to 13 volt setup.
by drawing the circuit of yours 'as is' and 'as shown' in you schematic, then you should be able to
reason out why the difference....and what ehose componenets do, per the handbook version.
The diagram for this supply was done by 621 electronics which no longer supports there web sight. Also Tenna was bought by Pyramid and both are defunk.
Re: Tenna phase III ps-20 power supply
an 18 volt zener will conduct if it gets a potential above 18 volts.
so what would be the reason a voltage on the pin of the 723 went above 18 volts, and was then tied to ground.
or effectively regulated to below 18 volts.
and what would be the results if it did go above 18 volts.. and stayed there. catastrophic failure???
so what would be the reason a voltage on the pin of the 723 went above 18 volts, and was then tied to ground.
or effectively regulated to below 18 volts.
and what would be the results if it did go above 18 volts.. and stayed there. catastrophic failure???