PL-259 to COAX can I use it

[oldticktock]

I had a rummage through the draws and found a PL259 but with an coax socket. Is it viable to cut the BNC from one end of a scope probe and solder on a coax plug?

I have two probes one is a HP2060 60mhz and the other is an RS.

Just itching to get going

Chris

[Kat Manton]

Hi,

Personally, I wouldn't destroy perfectly good 'scope probes. Good ones generally aren't cheap (even second-hand), they're useful and IME one can never have too many of them (I keep finding I'm one short anyway.)

(Just with one dual-trace 'scope, you might end up using three of them. Some frequency counters have inputs designed to work with 'scope probes as well.)

Just my 2d; if I need a plug with a bit of wire on it; I'll buy the plug and the wire rather than wreck something which is worth more.

(Since switching from 10Base2 to 100BaseT a years ago, I've chopped some redundant BNC-BNC cables in half to make odd test leads. That may be a better source of BNC cables than 'scope probes and it saves fitting BNC plugs to coax.)

Regards, Kat

[jimmc101]

I've got to agree with Kat, don't do it.
The cable used on 'scope probes is optimised for low capacitance and hence has a very thin inner, in fact some of the older Tek probes had a strand of resistance wire as the inner (to tame reflections). The junction between cable and plug is often a point of failure.
If your impatience gets the better of you, make up a Coax to BNC adaptor to get you started.
A Coax plug can be 'persuaded' to hold a BNC panel socket without too much difficulty.
Proper PL259 to BNC adaptors are available for £2-3 (ebay), you don't need a precision adaptor for a 'scope, impedance matching is not an issue.

Jim

[oldticktock]

Thanks all for the comments I shall wait. I ordered one expecting quick delivery only to get an automated replay about being on holiday for a couple of weeks. I shall use the time wisely and swot the scope manual.

[Kat Manton]

Hi,

Sorry; I misunderstood what you wanted to do.

My understanding is that length and type of cable have been acommodated in the design and they should be treated as a complete unit. Modifying them in any way is something I regard as generally not a good idea.

I'd prefer to trust the readings I get on the 'scope to some degree; a modified 'scope probe would IMO introduce extra 'unknowns'...

Regards, Kat

[chip-chop]

Just to agree with and add to the above, I think you'll find it tricky to say the least to re-terminate a 'scope lead connector cable, especially onto a coax plug, the inner wire is tiny on most of them and the outer is too small to get a reliable and secure physical connection to the plug body.

A PL259 plug to BNC socket adaptor if the only way to go.

[Dean Huster]

As a matter of fact, the inner center conductor of a good probe (even an X1 probe) is resistance wire and difficult to solder anyway. Inner insulation is often foam, so a lot of the scope-end termination is designed for good cable strain relief.

As mentioned, an adaptor with a male UHF on one end and female BNC on the other is easily found from many sources. It will not add enough capacitance to the scope input that you still can't properly compensate the probe.

NOW .... on the other hand .... back in the 1950s and early 1960s, Tektronix P6000-series probes had the option of BNC or UHF connectors. So you might cast around ebay and see if any of these UHF versions (P6006 for a 10X, P6028 for a 1X, P6007 for a 100X) are available. But since they'll be really old in the electronic sense, expect them to have a lot of damage or other problems! And don't misunderstand the parenthetical above: P6006, for instance, was available with a BNC or a UHF option. I didn't mean to infer than P6006, P6007 and P6028 all had UHF connectors. It all depended upon the part number.

Dean