[TCML] LBO-514A

[G Hunter <dogbrain_39560@xxxxxxxxx>]

All,

I'm seeking calibration info, or at least basic alignment info, for a LEADER LBO-514A oscilloscope.

Seeking a "coiling" oscope, I bought said unit from ebay for a song.  To my surprise, the scope arrived in very good condition--no rust, no dents, no cracked or missing knobs, no burned spots on CRT, plus a bright, sharp trace.  It's so cheap, I consider it "disposable", and I won't cry too much if life in close proximity to a Tesla coil kills it.

My only complaint is the lack of calibration.  Triggering & amplitude are fine.  The problem is nonlinearity in the horizontal axis.  Timing looks good on the left side of the display, but the test waveform bunches closer together on the right side of the display--as if the scope's sweep waveform itself is curved.  Weak sweep amp, perhaps?

I've scoured the WWW for cal info and found nothing.  With little to loose, I took the thing to work where I have access to trustworthy Tektronix oscopes and tech school-quality function generators.  With the cover off, I examined the various adjustment pots and found two likely prospects labeled "length" and "width" respectively.  I tweaked the "width" pot and got instant improvement.  I tried it with 1kHz, 10kHz, and 100kHz square waves, and eventually arrived at a reasonable compromise.

The thing is probably adequate for hobby-type coiling as-is.  However, it's in such nice condition inside & out, I'd really like to give it a proper alignment.  Can anyone help?  Got a link for me or a PDF you can email me?  If so, kindly contact me off-list.

Many Thanks,

Gregory R. Hunter


      
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