> 1 GHz DIY differential probes

[2N3055]

I would be interested too.
Nice work.

[mk_]

still working on my 400Mhz-diffprobe... I`m interested too

[nctnico]

I still have to update the PCB design to include the offset pot. I hope I can squeeze this in this week and then get a quotation from an assembler to have a couple of these probes produced professionally. It is not going to be really cheap (likely >100 euro) but still extremely competitive compared to 'the real deal'. I want to sell the probe as a kit complete with SMA to BNC cable, USB power cable and stainless steel wire to make probe tips.

[mk_]

I still have to update the PCB design to include the offset pot. I hope I can squeeze this in this week and then get a quotation from an assembler to have a couple of these probes produced professionally. It is not going to be really cheap (likely >100 euro) but still extremely competitive compared to 'the real deal'. I want to sell the probe as a kit complete with SMA to BNC cable, USB power cable and stainless steel wire to make probe tips.

At least here there are enough SMA>BNC-Cables aviable.

I use for my 400MHz-Probe something like this:
https://www.schukat.com/schukat/pdf.nsf/index/D796B48DFC770906C1257933002CFFBC/$file/PTR_Serie_1012_E.pdf

Anyway, 100€ are fine and if you need an assembler mail me PM, I`m working "inside" an assember....

[nctnico]

I still have to update the PCB design to include the offset pot. I hope I can squeeze this in this week and then get a quotation from an assembler to have a couple of these probes produced professionally. It is not going to be really cheap (likely >100 euro) but still extremely competitive compared to 'the real deal'. I want to sell the probe as a kit complete with SMA to BNC cable, USB power cable and stainless steel wire to make probe tips.

I just ordered a first batch of 10 pieces. The price for the complete kit is going to be 140 Euro including VAT. I'll create a user manual / specification sheet as well.

[bitbanger]

Expressing interest for one of these.

[BFX]

This is really great 
But isn't possible to do that in little bit better formfactor?
Slim to be able to put inside some nice aluminum cover? 

[nctnico]

This is really great 
But isn't possible to do that in little bit better formfactor?
Slim to be able to put inside some nice aluminum cover? 

I tried to make the board as narrow as possible however the width is dictated by the width of the micro-USB and SMA connectors. IMHO the design isn't lumpy compared to differential probes you can buy from R&S, Keysight or Lecroy but yes, it definitely is more lumpy than a passive probe. BTW I'm having a plastic case designed & manufactured because the heat-shrink sleeving just didn't sit right with me.

[mk_]

Slim to be able to put inside some nice aluminum cover? 

I buildt a 400MHz-Diffprobe some time ago and decided against a nice aluminiumcover because if it sits somewere on the circuit the chance for a destructive short is high.   

[BFX]

Slim to be able to put inside some nice aluminum cover? 

I buildt a 400MHz-Diffprobe some time ago and decided against a nice aluminiumcover because if it sits somewere on the circuit the chance for a destructive short is high.

It's all depends on design. If it's done properly there is no chance for some shorts. But yes it's necessary to have access to some CNC machine.
Here is for example my noise source.

[joeqsmith]

It's all depends on design. If it's done properly there is no chance for some shorts. But yes it's necessary to have access to some CNC machine.
Here is for example my noise source.

That's some nice work.

[mk_]

It's all depends on design. If it's done properly there is no chance for some shorts. But yes it's necessary to have access to some CNC machine.
Here is for example my noise source.

I didn`t mean short in the diffprobe itself but that the diffprobe, housed in an aluminiumcover and lying around can easily create shorts in the circuit it is probing below.
 

[David Hess]

A conductive case is actually desired to prevent degradation of the AC common mode rejection from variation in the probe's environment.  Plastic enclosures should have a conductive film on the inside.

[BravoV]

A conductive case is actually desired to prevent degradation of the AC common mode rejection from variation in the probe's environment.  Plastic enclosures should have a conductive film on the inside.

Will something like the old conductive carbon spray for coating the CRT TV case internal or the CRT tube work ?

Example :

[luma]

I’m definitely interested in placing an order when you think you’re ready for testers.  I have a fair bit of experience designing 3D printable enclosures for OSHW projects and would get to work on that immediately upon receipt of an assembled board.

[bitbanger]

^ with him/her. I'd be perfectly happy with as-is stated performance and 3D printing an enclosure.

[David Hess]

A conductive case is actually desired to prevent degradation of the AC common mode rejection from variation in the probe's environment.  Plastic enclosures should have a conductive film on the inside.

Will something like the old conductive carbon spray for coating the CRT TV case internal or the CRT tube work ?

Example :

If it will work for EMI shielding then it will probably work.  The cases on the Apple 2 computer used something like that on the inside.

[_Wim_]

A conductive case is actually desired to prevent degradation of the AC common mode rejection from variation in the probe's environment.  Plastic enclosures should have a conductive film on the inside.

Will something like the old conductive carbon spray for coating the CRT TV case internal or the CRT tube work ?

Example :

If it will work for EMI shielding then it will probably work.  The cases on the Apple 2 computer used something like that on the inside.

I think for EMI it is better to use this one on a plastic enclosure (kontakt chemie EMV 35 or EMI 35): https://uk.farnell.com/kontakt-chemie/emi-35-200ml/coating-conductive-emi-35-200ml/dp/2142398

[the Willows]

Very interesting, was on the way to order from the German guy, but this seems to be a much better design.
Please write me up for 2 pcs.

We own (me and Daniel from Xtreemtec) since last december a LeCroy WavePro 7300, but no probes yes. Hard to find item or huge prices.
So this is a good alternative.

[paul67]

Are there any probe kits remaining? I'm interested in one. Thanks.

[paul67]

I still have to update the PCB design to include the offset pot. I hope I can squeeze this in this week and then get a quotation from an assembler to have a couple of these probes produced professionally. It is not going to be really cheap (likely >100 euro) but still extremely competitive compared to 'the real deal'. I want to sell the probe as a kit complete with SMA to BNC cable, USB power cable and stainless steel wire to make probe tips.

I just ordered a first batch of 10 pieces. The price for the complete kit is going to be 140 Euro including VAT. I'll create a user manual / specification sheet as well.

Meant to 'quote' that. I'm interested in one of those probe kits...

[nctnico]

I'm almost ready to put the first batch together. Give me a few more days to make the official announcement.

[technogeeky]

I'm almost ready to put the first batch together. Give me a few more days to make the official announcement.

I'm also interested.

[the Willows]

Tonnie Wittenaar wrote on the 4th of January:

Very interesting, was on the way to order from the German guy, but this seems to be a much better design.
Please write me up for 2 pcs.

So if Designer can give us an update how things are going, or project has died, please let us now.

[nctnico]

Nearly ready! Everything except the SMA to BNC cables has been delivered. The boards have been tested and adjusted. I'm going to assemble the first batch in the next couple of days. The datasheet is also nearly ready. I want to do a few more measurements regarding spurs and noise.