I‘m making 100 Meg(+) standard resistors(and as 10+ Meg Hamons as well)

[acbern]

Great! What are the mating connectors for the BNCs?

[zlymex]

Great! What are the mating connectors for the BNCs?

Thanks. Those connectors are of special male type often found on test fixtures of LCR meters.

[acbern]

Yes, I know, but where did you get these from? Is there any part reference (other than from Keysight?).

[Gyro]

Same question here, where can you get them? That's an impressive alignment, I understand now why you had boards made!

[zlymex]

I bought them from Taobao(China ebay) about two years ago but running out, I've just bought some more from here:
https://item.taobao.com/item.htm?id=45440995167

There is another way as some one has suggested: buy regular BNC male plugs(with PCB mount) such like these(very cheap):
https://item.taobao.com/item.htm?spm=a1z0d.6639537.1997196601.230.Wi4im5&id=14163363960
and remove the mounting heads yourself after.  I've tried this before by two ways, one is by pure force, the other is to gradually lever at the end by s screw driver to let loose the spring, the whole thing will come out.

Edit: I found some entries at aliexpress selling the same thing such as:
http://www.aliexpress.com/item/Quick-TNC-or-BNC-male-nut-bulkhead-deck-mount-solder-cup-RF-connector/32619733999.html

Don't buy those with straight head as they often don't contact female sockets such as:
http://www.aliexpress.com/item/RF-electrical-terminal-connector-BNC-Plug-panel-mount-Quick-Push-on-bulkhead-with-Solder-cup-connector/32443473110.html

[zlymex]

Update: common Hamon adapters finished. They are common so that they can be used for all my Hamons to facilitate parallel, series and mixed connections.

If one of the adapters connect to the short Hamon body, the total height is 67mm

[doktor pyta]

Zlymex, fantastic job

P.S. Have You considered using typical laminate with copper (etched only near the connectors). Since You have guard rings this could provide better electrostatic shield. Was it due to the higher cost of this solution or the leakage in the guard divider string ? 

[zlymex]

Zlymex, fantastic job

P.S. Have You considered using typical laminate with copper (etched only near the connectors). Since You have guard rings this could provide better electrostatic shield. Was it due to the higher cost of this solution or the leakage in the guard divider string ?

Thanks very much. Probably I did not quite follow you, did you mean to cover large part of the board(probably both sides) with copper? I did plan this, and with copper ring on both side around the connectors, and make isolation rings to separate the guard and earth. That certainly works better. However, the insertion and separation of top part require a tremendous force, board of 3mm thick has to be used, the PCB manufacturer don't seem to do PCBs of this thick(usually 1mm to 2mm), I have to buy bare FR$ board(without copper layers, in any thickness such as 10mm) myself and had them cut by CNC machine.

In my current version, there is a gap between top and bottom which might affect the guarding connectors(which are high impedance) as well. I'm going to use flexible, insulated, earth-connected copper foils to wrap around the gap if that is a problem.

[doktor pyta]

Yes, I got my answer
Thanks.

[leighcorrigall]

I assembled a table of high value resistance, not meant accurate nor complete, just for reference.

Hi zlymex,

I realize that this topic is a little old, but do you have a more updated version of your spreadsheet? I am particularly interested in the Ohmite RX-1M temperature coefficients. How did you quantitatively determine the temperature coefficient increases as a function of increasing resistance? This is not included in the datasheet.

Also, can you please provide websites to the other manufacturers listed? Some of them I cannot find and am unfamiliar with.

Thank you!