Power Supply Project Begginer help

Thread Starter

raynmanSD

Joined Mar 5, 2011
2
I am building a power supply according to G. Randy Slones Guide to electronics. I just got through connecting the bridge rectifier and I am getting correct readings on measuring DC voltage (+24volts and -24volts), but my AC volt readings measure +54 volts and 0 volts not +12 volts AC for each reading as the author expects.

Attached is the schematic. I am taking the readings with black DVM lead attached to the circuit common and the red lead connected to the negative output of the BR for reading 1 (0 volts ac), and the positive output for reading 2 (+54 volts ac).

This is the first time my readings did not match the authors and I am stumped on what to do.

Thanks for any help.
 

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SgtWookie

Joined Jul 17, 2007
22,230
You don't actually have the black DVM lead attached to the circuit common ground; you have it connected to one of the "ends" of the secondary winding.
 

Thread Starter

raynmanSD

Joined Mar 5, 2011
2
Sorry I don't no why I added Ground what I meant to say was the circuit common connection (which I took to mean the connection between the 2 transformers via there secondary leads.)
 

Kermit2

Joined Feb 5, 2010
4,162
measure the AC at the output leads of the transformer(secondary) or at the input of the rectifier. The ground is AFTER the diode so using it will NOT show a true AC voltage

using the ground will only show you DC components of the AC signal
 
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