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Products => Other Equipment & Products => Topic started by: WT4DX on April 10, 2024, 03:08:19 am

Title: 50 Ohm RF Terminators
Post by: WT4DX on April 10, 2024, 03:08:19 am
Is there one company that makes a consistently more accurate 50 ohm RF terminator over another?
Title: Re: 50 Ohm RF Terminators
Post by: shabaz on April 10, 2024, 03:42:01 am
Most no-name BNC ones are best avoided, since they are likely intended for old LAN setups, and are not very wideband.

The 50 ohm terminators/loads with a datasheet will be best, because you can examine that to see if it meets your needs (they will have a chart or table of return loss values). Examples are Minicircuits (generally affordable) or Huber+Suhner (might be a bit more expensive). Other examples off the top of my head that may offer them are MACOM, Radiall, Rosenberger, I've not purchased 50 ohm terminators/loads from them though. I'm sure there are even more exotic suppliers.

I've bought 50-ohm loads from Minicircuits if it's cost-sensitive (but it is still backed up by a datasheet), otherwise Huber+Suhner. Both are available from normal electronics distributors usually (or can buy direct from Minicircuits).
Title: Re: 50 Ohm RF Terminators
Post by: Wallace Gasiewicz on April 10, 2024, 11:28:25 pm
Shabaz is correct, in my experience,.  BNC are usually not good for higher freq.   

I have a bunch of BNC 50 ohm loads Brand Name,  Amphenol. as I remember, good to maybe 50 MHz   

Also a bunch of Huber Suhner SMA loads good to over 3 GHz,  This is as far as I can test.
I have lots of both, new in packages,  if you want some.
Title: Re: 50 Ohm RF Terminators
Post by: jonpaul on April 12, 2024, 11:10:28 am
The best are old Tektronix 50 Ohm BNC 0.5W

Most accurate are vintage EG&G with 0.1% accuracty.

We use Mini-Circuits excellent HAT-xx+ (xx = attn in db)

DC-2 GHz, fine construction, just $10 and small orders easy.


https://www.minicircuits.com/WebStore/terminations.html (https://www.minicircuits.com/WebStore/terminations.html)

Made in amy power levels, BW and connectors, eg SMA, N, BNC.

ENjoy,


Jon
Title: Re: 50 Ohm RF Terminators
Post by: WT4DX on April 12, 2024, 05:30:14 pm
What is an acceptable accuracy tolerance for a 50 ohm terminator?

Thanks,
Tem
Title: Re: 50 Ohm RF Terminators
Post by: WT4DX on April 13, 2024, 04:43:09 pm
Does anyone own this N-Type Huber+Suhner terminator (65_N-50-0-1/133_NE)?

If so, would you tell me the average return loss in the 1MHz -1GHz range?

Thanks,
Tem
Title: Re: 50 Ohm RF Terminators
Post by: jonpaul on April 14, 2024, 12:57:12 am
Tem: Accuracy:

Rtn loss is only slightly affected if term is off bu a few %

DC accuracy to test eg Scope input Zo, should e at least 1%

It possible to have a fine wideband RL but the DC R and accuracy is not perfect.

Our old EG&G have 3 digit cal eg 51.1 Ohm.

The TEK can be off 2 %

Jon

Jon