Re: Oscilloscope arrived - black market sucks

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Crow Leader" <tesla-at-lists.symmetric-dot-net> 

I'm sure it was mentioned in this thread before, but transformers with no
load can have really ODD waveforms. I was working with a boring sand potted
1.5kVA 480/240/120 transformer and the output waves were not sine at all
until I added a few watts of load with a lightbulb.

KEN


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, April 05, 2004 8:25 AM
Subject: Re: Oscilloscope arrived - black market sucks


 > Original poster: Skip Malley <skip-at-ladybughell-dot-com>
 >
 > If you connected a transformer rated at 9VAC output to the input of your
 > new O-scope, It would be likely that you would see a sine wave of
 > approximately 15V peak.  A transformer with a rated 9VAC output into a
 > certain load would likely show what you have described.  The transformer
is
 > rated to be 9VAC at a certain load.  That is the RMS value.  The peak
 > voltage would be approximately 1.4 times the RMS (rated) value.  If your
 > transformer has no load, then the voltage would be a bit higher.
 >
 > 15 V peak or 30V peak to peak would be expected from a 9VAC transformer.
 >
 > How are you connecting diodes???
 >
 > Skip
 >
 >
 > At 01:04 PM 4/4/2004 -0600, you wrote:
 > >Original poster: Kreso Bukvic <kreso.bukvic-at-kc.htnet.hr>
 > >After playing with my new scope for almost whole night it look like it is
 > >not good!
 > >
 > >What should i check before i beat the crap from the black market seller?
 > >:-))
 > >
 > >What are the basic check steps to see if it is good?
 > >
 > >I tried conecting 9 VAC transformer at input, scope measures 15 V with
odd
 > >showing, ok i tried adding one diode no improwment 2 dioes nothing,
greatz
 > >then i get only a line it cannot be a line only with a greatz - right? It
 > >cannot be full DC with only 4 diodes? Or when i touch the table the
waveform
 > >gose here and there it moves by it self, scope is not fizically connected
to
 > >table it does  alot of crap etc and etc.
 > >
 > >Help
 > >
 > >Best Regards
 > >
 > >Kreso Bukvic
 >
 >
 >
 >
 >