Can scope probe extension cable be used ...

[beppe61]

... as cable for low level signals ?
Sometimes at electronic fairs I find coils of cables for scope probes and I wonder if this kind of 50ohm cable could serve well as audio cable.
After all it is expected to pass square waveforms up to Ghz, isn't it ?
Opinion would be very welcome and appreciated.
Thank you sincerely and kind regards,

bg

[Lord Winter]

Indeed !

Quality scope cables might be better than $$$ Nordost junk.

[beppe61]

Originally posted by Lord Winter

Indeed !
Quality scope cables might be better than $$$ Nordost junk.

Thank you very much Sir.
Do you have direct experience of them as signal cables?
Could you give me some info about their structure (are they solid core)?
Are they easy to solder to RCAs ?

Thank you and kind regards,
beppe

[Lord Winter]

No Beppe, I dont have any firsthand experience with these, however the source of this "hint" is an old audio junkye, perhaps he knows better.
Just think of it: these cables were made for perfection, to conduct complex, high frequency waveforms with minimal losses.

Solid core or stranded.

Again, I can just guess. If solid core, they must have a fairly thin conductor to remain elastic.

Recommended reading:Cable nonsense

Have faith and experiment, remember: no pain - no gain !

[beppe61]

Originally posted by Lord Winter
No Beppe, I dont have any firsthand experience with these, however the source of this "hint" is an old audio junkye, perhaps he knows better.
Just think of it: these cables were made for perfection, to conduct complex, high frequency waveforms with minimal losses.
Solid core or stranded.
Again, I can just guess. If solid core, they must have a fairly thin conductor to remain elastic.
Recommended reading:Cable nonsense
Have faith and experiment, remember: no pain - no gain !

Thank you very much again Sir.
This deserves definitely a try.
Kind regards,
beppe

[Elvee]

Hi

Oscilloscope probe cables have very peculiar features that make them totally unusable for any other application: they are high impedance and have a decreased conductance in order to display a flat frequency response when associated with a typical 1M/25pF load.
In practice, to achieve this high impedance and high losses, the inner conductor has a very low diameter (<0.1mm) and is made not of copper but a special resistive alloy; this give a resistivity of more than 100ohm/meter.
Associating a significant length of such a cable with a typical audio input impedance would result in serious alterations of the signal.
In addition, it is a nightmare to use: the inner conductor is not only very thin, but also made of a non-solderable alloy.
LV

[Lord Winter]

Dammit Elvee, you're right !

I just checked one daewoo cable, 1,2m long, and it had 165 ohms of resistance. Still, it's worth trying, if the soldering can be omitted somehow...

[beppe61]

Dear Sirs,


thank you very much for your very valuable advice.
So probe extension cables are not good.
What about good quality coaxial for sat TV ?
The specs look good.
As you can very well understand I am trying to save money on cables.

Kind regards,

beppe

[Elvee]

Coaxial cables are optimized for regularity of characteristic impedance and low losses at SHF, none of which is particularly useful or relevant at audio frequencies.
In addition, satellite cables often have an alumium sheet held by shallow inox steel strands as outer conductor and and a copper- or silver-plated steel inner conductor. I have an intuitive dislike for both features. Add to that the fact they are thick, stiff and awkward to handle...
Well, do as you please, but this is certainly not my cup of tea.
Oh, I forgot something: the insulator is not continuous, but is either a spiral or a star or something like that, with plenty of interfaces of polyethylene with air, PE with metal, which must generate nice electric charges at the slightest movement... must be wonderfully microphonic, I guess you could turn one into an electric drum or something.
Have good fun,
LV

[beppe61]

Originally posted by Elvee
Coaxial cables are optimized for regularity of characteristic impedance and low losses at SHF, none of which is particularly useful or relevant at audio frequencies.
In addition, satellite cables often have an alumium sheet held by shallow inox steel strands as outer conductor and and a copper- or silver-plated steel inner conductor. I have an intuitive dislike for both features.
Add to that the fact they are thick, stiff and awkward to handle...
Well, do as you please, but this is certainly not my cup of tea.
Oh, I forgot something: the insulator is not continuous, but is either a spiral or a star or something like that, with plenty of interfaces of polyethylene with air, PE with metal, which must generate nice electric charges at the slightest movement... must be wonderfully microphonic, I guess you could turn one into an electric drum or something.
Have good fun,
LV

Thank you very much Sir for your extremely kind and valuable advice.
May I ask you which would be your first choice of a bulk cable to make some DIY interconnects?
I would like to try to build something by myself.

Thank you very much indeed.
Kind regards,

beppe