[Boatanchors] Inexpensive Scope Probes

[rbethman]

I don't know how long it has been since you were in the Navy.  If you 
are like a large number of us, it has been a couple or more decades 
since we left the military.

I would "normally" agree that non-spec items are to be shied away from.

I went ahead and bought the same ones that are being offered currently.  
(It is 2011 now....)

I attached these new ones to the dual channel inputs, along with an 
Honest to goodness Tektronix Probe.

Both got fed a 38.8 MHz PLL circuit test point.

I swapped them back and forth from ch1 to ch2.  Running my hands over 
them, and even twisting them around each other resulted NO CHANGE in 
waveform.  The same result even when wrapped under the chassis of the 
mainframe of the Tek 5440.

They also compensate very well.

Since I'm savings significantly, I'll go ahead an use them.  *IF* there 
is an "unseen" difference on traces, when one is laid over the other, it 
has got to be about 1% or less.

I think they are more than usable for Amateur Radio.  The larger number 
of us are working on our own equipment.  We don't have a need for NIST 
traceability.

You'll find the nuts and bolts you buy are loaded with "forgeries", and 
that they will NOT hold the same torques.  I worry more about that when 
I start to bolt together 400 pound or greater pieces of gear.

YMMV.

Enjoy,
Bob - N0DGN

On 2/8/2011 11:25 PM, Glenn Little WB4UIV wrote:
> While in the navy, we ordered a Tektronix scope probe.
> Due to competitive bids and "specs" we received a knock off probe.
> When I attempted to measure a clock waveform in a computer with the
> prescribed scope and this probe, the waveform would change depending
> on where along the lead you placed your hand or the position of the
> lead relative to the chassis of the computer.
> The next order was specified "do not substitute" and we did receive a
> genuine Tektronix probe.
> There was no problem measuring the clock waveform with this probe.
>
> Buyer be ware with cheap probes.
> Probably useable for audio, but very questionable above a few MegaHertz.
>
> It all depends on how much you want to trust the waveform displayed
> on the scope to be an accurate representation of the measured circuit.
>
> Just my experience.
> I will only use quality probes.
>
> 73
> Glenn
> WB4UIV