What coax cables / accessories to get ? - Page 1
Forum section: electronics / testgear

author: MathWizard
author_rank: Super Contributor
timestamp: September 10, 2021, 11:59:53 am
content: I have a 2Ch function generator thats good up to 120MHz, and a 200MHz BW scope that has a spectrum analyzer FFT mode. But I don't have any coax cable or proper accessories for the AWG, I've been just using $5 alligator clips with a BNC on 1 end. It's about time I get the proper stuff, so I can use it all better.Are there kits you can buy ? I don't want to just look on ebay or Amazon, but I hope a few accessories won't cost $100's either. I don't want to buy more tools either (for lack of space)

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: September 10, 2021, 12:44:24 pm
content: I make my own. I use RG 223 double shielded coax. I think the BNC crimp connectors are a good choice. I have tried some of the old type multi part solder connectors that are a real pain to install, but work well if installed well.The coax cables with aluminum foil wrap sometimes "break" the foil with frequent handling, the same goes for anything with an aluminum central conductor.Any real good RG 58 would also be fine for below 200MHz.The half inch cables are better in terms of freq and loss but are generally too big for easy use. I do use come of these.For short test cables LOSS is not really a big deal since you are using such a short run.Maybe buy this and cut it down and make several shorter test jumpers.https://www.ebay.com/itm/164360158492?hash=item2644a0fd1c:g:u4cAAOSwNYFfS8Ek

author: figurativelythedevil
author_rank: Contributor
timestamp: September 10, 2021, 01:58:48 pm
content: For those frequencies, most coaxial cables will be fine. Just make sure to use 50cable/connectors, there's a lot of cheap 75cable out there. I'd recommend something with a stranded center conductor if you're using it as a jumper. Personally, I really like LMR-240-UF, nice and flexible and not super expensive.https://www.pasternack.com/showProduct.aspx?SEName=bnc-male-bnc-male-lmr240uf-cable-assembly-pe3c0987&ProductID=This is a 4ft BNC assembly made by Pasternack, it's a little pricey, but not too bad. If you do have the ability to make your own cables though, I'd recommend it, but the up-front gear cost is gonna bite. As Wallace said, RG-58 would also be perfectly fine, and is pretty widely available.

author: tautech
author_rank: Super Contributor
timestamp: September 10, 2021, 11:31:21 pm
content: Quote from: MathWizard on September 10, 2021, 11:59:53 amSiglent's 1 GHz BNC cables are not expensive:https://siglentna.com/products/accessories/cables/

author: tkamiya
author_rank: Super Contributor
timestamp: September 11, 2021, 05:23:45 am
content: For that kind of frequency, just about anything will work.My only advise would be to avoid CHEAP Chinese junk that doesn't fit all that well. Not all made in China stuff are junk, by the way. RG58 of any kind is plenty available from various sources.For your scope, please be careful! If you select 50 ohm input, it is so easy to burn that out. Typical impedance is 1Meg Ohms, which usually means you'll be using a proper probe. Most of my probes came from Amazon. They work well enough for my purpose.

author: Cerebus
author_rank: Super Contributor
timestamp: September 11, 2021, 03:24:12 pm
content: I got some reasonable quality 1m BNC <=> RG316 <=> BNC cables fromhereon Aliexpress the other week for the princely price of £2.46 GBP each. I've been using them (only at 10MHz) for a couple of weeks without any issues. The BNCs fit nicely on all my test equipment (respectable names like HP), which can't be said for some of the cheap BNCs that come out of the Middle Kingdom.RG316 might be a bit stiff for some people's taste but generally I prefer it on the bench as I find that it's a little less likely than RG58 to get tangled up when you've got a lot of leads on the go at once. Also the stiffness encourages me to actively route cables as I'm working rather than just pulling a length of RG58 around too tight corners or leaving it in tangled heap and the like.

author: MathWizard
author_rank: Super Contributor
timestamp: September 11, 2021, 05:38:36 pm
content: I'm watching stuff like this, and Dave is talking mostly about sub 200MHzI don't know enough to know what I need yet. Plus I'm still pretty new to scopes/etc.If I was to work on an FM radio (receiver), I have nice +200MHz 10x scope probes, if I try to use 100MHz from the AWG to test some circuit, what should you really be using if you what to make accurate measurements ?

author: tkamiya
author_rank: Super Contributor
timestamp: September 11, 2021, 06:01:19 pm
content: AWG is really not suitable for what you are going to do. RF signal generator would be much more useful.Cable wise, all you need is some kind of coax with both ends with suitable (BNC?) connectors. Oscilloscope probes of proper rating. That's about it. Most of the time, you really don't need accurate measurements. Relative measurement is often sufficient. My suggestion is not to get ahead of yourself. Add small piece at a time.What Amazon sells are not the best. But I consider probes and cables semi-disposable. Sure, generic probes has limits and HP probes are better, but do you really care little attenuation and such? I don't. Once you get a hang of it, you can start buying specific probes that suites your projects. There are many types. They are fairly expensive. Not something you want to casually buy.

author: nctnico
author_rank: Super Contributor
timestamp: September 11, 2021, 06:08:28 pm
content: Quote from: MathWizard on September 10, 2021, 11:59:53 amI buy all my coax cables from this website:https://rfbat.com/For your frequency range RG316 (which is thin and flexible but not too thin) is more than good enough. Thin cables are easy to work with. Thick coax like RG58 is not very pleasant to use on a workbench.

author: Rod
author_rank: Contributor
timestamp: September 11, 2021, 08:45:44 pm
content: Alan Wolke, w2aew, has created an excellent series of videos...Dave's goal is more entertainment. Alan's goal is more educational.

author: DaJMasta
author_rank: Super Contributor
timestamp: September 11, 2021, 09:06:21 pm
content: You can often get new old stock Pomona leads on ebay, and it's nice to have some BNC to banana adapters (or BNC to spring hook or both), but I'd say get a couple of leads, a tee, maybe a 50 ohm termination, and then just whatever's needed for your project - you'll accumulate plenty.Also worth noting that while preterminated cables seem to be cheaper as new old stock, very often adapters aren't. If I need BNC to whatever adapters, I'll usually just buy from a major distributor who will give me a datasheet for a part - it is often cheaper than the old stock equivalents.Make sure that you're buying 50 ohm coax for using with your equipment though, and if you need to connect to 75 ohm systems, I like to mark the cables as such. Won't matter for a lot of cases, but as you get higher in frequency it will make a difference.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 30, 2025, 07:44:42 pm
content: This is absolutely a rabbit hole, but it's kinda fun too. I've been getting cables/connectors fromhttps://messi.it/. They can make custom cables for you if you don't want to make them yourself, and they're pretty reasonably priced.