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KC2UGV
03-27-2015, 01:35 PM
So, I picked up my first o-scope, mainly for logic testing. So, I've figured out how to do that, but as a ham, what other tactics should I be whipping this unit out for? It's a Ramsey 2200 ($40 from an estate sale, I think I got a pretty ok deal on it), and comes equipped with a probe already.

And, should I bother getting a spare set of probes, or are these things pretty hardy?

N8YX
03-27-2015, 01:45 PM
Look into building a line sampler for use in examining your transmitted RF waveform.

Does your HF rig have an IF Out whose frequency is lower than the scope's maximum vertical bandwidth? Connect it to the radio via good quality shielded coaxial cable and look at off-air signals.

Do you still have the PK-232s I sent up? They have a tuning indicator output, accessible via the 5-pin DIN connector IIRC. Put the scope's timebase control (sweep) in Ext Horizontal mode, connect the Mark line to the Vertical input and the Space to the Horizontal, adjust the vertical sensitivity so the two signals are roughly the same amplitude then tune for "crossed ellipses".

There are many more uses...I'll let the others chime in here too.

K7SGJ
03-27-2015, 01:51 PM
Not familiar with the Ramsey, but I'd just use them till they break and can't be fixed any more. There are all kinds of things that you can do. Looking at your audio for distortion comes to mind. Plus there are all kind of little add ons that can be useful. If you google curve tracer, there are all kinds of simple circuits to allow you to look at semiconductor junctions as well as capacitor and other component signatures. I don't know how high it goes in frequency, but if it goes into the rf region, you can build a simple sampler circuit to look at your transmitted signal. And, with the right adapter, you can pick up some pron channels.

K7SGJ
03-27-2015, 01:53 PM
Look into building a line sampler for use in examining your transmitted RF waveform.

Does your HF rig have an IF Out whose frequency is lower than the scope's maximum vertical bandwidth? Connect it to the radio via good quality shielded coaxial cable and look at off-air signals.

Do you still have the PK-232s I sent up? They have a tuning indicator output, accessible via the 5-pin DIN connector IIRC. Put the scope's timebase control (sweep) in Ext Horizontal mode, connect the Mark line to the Vertical input and the Space to the Horizontal, adjust the vertical sensitivity so the two signals are roughly the same amplitude then tune for "crossed ellipses".

There are many more uses...I'll let the others chime in here too.


Damnit Fred, get off my frequency. :stickpoke::stickpoke:

WTKX
03-27-2015, 02:06 PM
http://www.nu9n.com/scope_your_audio.html (http://www.nu9n.com/scope_your_audio.html)

http://n9sja.com/2013/10/06/rf-oscilloscope-sampler/

suddenseer
03-27-2015, 04:57 PM
Those look like what we had on our benches back in com/elec classes. Get a sampler cir.....um never mind.

N8YX
03-27-2015, 05:18 PM
Your next scope should be a Tektronix 7000 series. Then get some plugins for it.

Shown here is a 7603, arguably the most readily available of the lot. 100MHz B/W. Installed is a 7L13 1.8GHz spectrum analyzer plugin:

13784

N8YX
03-27-2015, 05:23 PM
7D01 logic analyzer plugin. 16 channels.

13785

N8YX
03-27-2015, 05:30 PM
7CT1N curve tracer. Checks diodes, transistors, FETs and so forth with accessory test fixtures.

13786

N8YX
03-27-2015, 05:36 PM
7S12 TDR plugin. Use this to find impedance bumps and breaks in your transmission lines.

13787

WTKX
03-27-2015, 05:40 PM
Oscope pr0n.

N8YX
03-27-2015, 06:08 PM
Oscope pr0n.
Hard-core o'scope pr0n...now with clock!

ETA: this gadget does much more than display the time...and I think that one or two might make their way into my SB-series scope hacks.

https://www.sparkfun.com/products/9306

13788

KC2UGV
03-27-2015, 06:38 PM
Oh, by all means, I know I didn't get a cadillac of O-scopes :) I got something pretty basic, which covered at least getting used to it, and rumors say it's all through hole, and uses parts still available today.

Some of you folk would have drooled over what this estate sale had too: HO/O/N trains/parts/tracks/etc, retro gaming galore, and he had a ton of telco gear (Butt sets, tone tracers, crimps, punch downs, pole spikes, etc etc), and a ton more. One of the better ones I've been too. Shockingly, no ham gear though? I guess he had his plate full with his hobbies already lol

N8YX
03-28-2015, 11:18 AM
Oh, by all means, I know I didn't get a cadillac of O-scopes :) I got something pretty basic, which covered at least getting used to it, and rumors say it's all through hole, and uses parts still available today.
And

It's a Ramsey 2200 ($40 from an estate sale, I think I got a pretty ok deal on it)

You did fine - one can never have too many scopes! I probably have 30 Tektronix SC50x and MR501 scope plugins in addition to my 7000 series gear - and that doesn't take into account the collection of various scope accessories which Heathkit, Kenwood and Yaesu produced.

I brought up the 7603 for a reason: Keep your eye on Craigslist. A working 7603 and 7D20 (2 channel digitizer) plugin went for $60 from a seller in the Chicago area, and that's about half the going rate for the plugin alone.

suddenseer
03-28-2015, 01:10 PM
his is all in YX's lab, trust me. I was there. He has more testing equipment than most metrology labs have on hand.