Banana Jack to J Hook Lead Length

[bostonman]

I have a silly question.

Most of my cables (J hook to J hook) are around 2' in length. I'm looking for banana to J-hook to go from a power supply to cricuits (I'm tired of hacking connections and having them fall off), and, while placing an order on Amazon, thought to add some to my order. All I'm finding are 3.3' (39") long.

Correct me if I'm wrong, but these are too long and they'll end up dropping too much voltage over this distance along with noise, correct?

For whatever reason, Amazon will not find 18" or 24" even though I put that in the search. I'm resorting to DigiKey or Mouser in a bit, but wanted to confirm I'm not crazy and searching for ones too short; and that maybe I should just buy these.

[jonpaul]

DC/audio: No effect, cable cap os 100..300 pF/ft.

RF/HF above 100 kHz use 50 Ohm RG/174/U or RG/58/U 50 Ohm Zo and termiante with 50 Ohm

Then legnth is only slight attenuation.

For test of PSU, SNPS 3', 1 M very common.

Better to AVOID cheap ChiCom junk on Amazon, ebay has fine Pomona calbes old ones made in USA


Enjoy,

Jon

[bostonman]

My 18" and 24" have been measured to drop some good amount of voltage.

Obviously I could have calculated the drop, but when I began seeing 39" ones on Amazon, I began wondering if this is the new standard.

I'll look into the Pomona Cables, good feedback. Thanks!

[ajb]

Voltage drop isn't just a property of the wire.  Any conductor will show a voltage drop if you pass enough current through it.  So if the circuit you're powering consumes a significant amount of current, your leads need to be up to the task.  The limiting factor on cheap test leads is often the termination.  I've seen some where the wire is just wrapped around the test clip and held in place by the plastic shroud.  Others may have surprisingly little metal for the size of the wire.  Resistance between the hook and whatever it's attached to may also be significant, I wouldn't generally want a J-hook on more than one end. 

Longer wires are more susceptible to noise in the sense that there is more of them and therefore more exposure to whatever's going on around them, plus more impedance, but 2ft -> 1m isn't likely to matter. 

[David Hess]

You can always buy the banana jacks and j-hooks separately and make your own, with whatever gauge wire is suitable.  Or cut and splice the ones you can buy to make them shorter.

[bostonman]

You can always buy the banana jacks and j-hooks separately and make your own, with whatever gauge wire is suitable.  Or cut and splice the ones you can buy to make them shorter.

I agree and considered that.

Over the recent years I've begun growing frustrated having a power supply with a banana jack and only having J-hook. I end up wrapping a resistor around and clipping onto it, however, it sometimes loosens. After tolerating it for so long, I added banana to J-hook to my shopping list.

[Xena E]

I used to cut and shut leads to suit my needs at work, those available to me were good quality ones, now the bean counters have even got to that and we have had a consignment of junk ones that have CU plated ALU conductors...

Complete junk.

Buy cheap, buy twice: just saying.

Time suck I know, but perhaps better the OP make up their own and choose the wire to suit the task?

[MarkF]

I bought these from Amazon:

Elenco TL-12, Banana to Mingrabber Test Lead Set
  https://www.amazon.com/gp/product/B0002JJU3C/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1
Elenco TL-5, Banana to Alligator Test Lead Set
  https://www.amazon.com/gp/product/B0002JJU1O/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
Elenco TL-18, Banana to Banana Test Lead Set
  https://www.amazon.com/gp/product/B0002JJU4Q/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

[TERRA Operative]

I tend to make my own cables.

I buy silicon insulated copper cables as used in battery packs and cabling in remote controlled cars and planes etc, then solder on my own connectors.
That way I get nice and thick super flexible copper cables and whatever connectors I specifically need.

[bostonman]

I"m actually shocked banana to J-lead isn't in my collection.

Sometimes I get lazy and just use what is close by, but I looked in my box of "multimeter" connectors and realized banana jacks aren't in the inventory.

Months ago I put resistor leads in all my power supply connectors, but nothing beats the solid connection of a banana jack plugged into it. No need to try figuring out why you're not measuring voltage only to discover the lead came off (or out) of the power supply. Or using alligator clips jammed into the banana jack.

[David Hess]

You can always buy the banana jacks and j-hooks separately and make your own, with whatever gauge wire is suitable.  Or cut and splice the ones you can buy to make them shorter.

I agree and considered that.

Over the recent years I've begun growing frustrated having a power supply with a banana jack and only having J-hook. I end up wrapping a resistor around and clipping onto it, however, it sometimes loosens. After tolerating it for so long, I added banana to J-hook to my shopping list.

I have been cutting my test lead sets in the middle and inserting Powerpole connectors, so I can swap the plug end with the clips end between all of my test lead sets.  Normally this would not be necessary, however there are at least 4 different standards now for banana plugs which are not all interchangeable; the shroud diameters and lengths vary.

I buy silicon insulated copper cables as used in battery packs and cabling in remote controlled cars and planes etc, then solder on my own connectors.  That way I get nice and thick super flexible copper cables and whatever connectors I specifically need.

I will have to check out that source for test lead wire.  I have a couple of spools of old school black and red rubber insulated test lead wire, but the rubber does not last forever.

[watchmaker]

I just went through this.  I got annoyed with two different jack systems.  I bought adapters for my PSU outputs and redid all leads to the sheathed plugs.  I made my own J hooks out of 16 stranded and 20 solid for this reason as well.  Some 12s, 24s and 36s.

And various colors to keep my sanity.  Cable mgt seems to be my Kryptonite.

Still stuck with 3 probe systems (slip on, threaded and plug), but at least I can easily kill a circuit.

[reboots]

39 inches sounds like 1 meter, converted for the US market.

I use Pomona 3782 minigrabber (J hook) to stacking banana plug cables, which come in multiples of 12 inches. Each of my bench power supplies is outfitted with different cable colors. If current load is high enough for voltage drop to be a concern, I use heavier wire direct to the binding posts.

https://www.pomonaelectronics.com/products/patch-cords/minigrabber-test-clip-stacking-banana-plug

I also have the Pomona 5523 10-color kit of their 3781 minigrabber to minigrabber cables, for general patching.

Pomona products are expensive, but very good quality. Life is too short to wrestle with poor connections.

[bostonman]

39 inches sounds like 1 meter, converted for the US market.

I agree.

Most of my cables are around 18" to 24", so I thought it was amusing these are 39", however, as I kept searching, it appeared this was the standard length.

[Kanbus]

Hooks:
https://www.digikey.com/en/products/detail/e-z-hook/X100WBLK/528234
https://www.digikey.com/en/products/detail/e-z-hook/X100WRED/528235
They are gold plated for good contact. Bare copper will oxidize and increase contact resistance.

Banana plugs:
https://www.digikey.com/en/products/detail/mueller-electric-co/BU-P1825-2/4073758
https://www.digikey.com/en/products/detail/mueller-electric-co/BU-P1825-0/4073756
I like that they are stackable. Look in the datasheet for the real plug
https://www.muellerelectric.com/product_files/887/DS-BU-P1825-@.pdf.
Digikey shows the wrong picture.

16 AWG cable:
https://www.digikey.dk/da/products/detail/dfrobot/FIT0584/9559253
Or buy silicone cable from eBay. It's cheaper and tends too be fine.

About 14$ for a quality set of cables.
Make a set or two. They will last for years.