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Locked Re: Half LZ1AQ Transistor Noise Output at LF and Norton 10 MHz gain and NF comments

 

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I have both OnSemi and Motorola and tested both of them--they were identical for both LF noise and 10Mc NF.

Steve

On 9/6/2022 11:12 PM, Fred M wrote:

One question Steve, regarding the transistor noise list.
Was the recently tested PZT2222A an ONSemi oder an NXP/Nexperia (PZT2222A,115) transistor?

regards
Fred

Locked Re: Half LZ1AQ Transistor Noise Output at LF and Norton 10 MHz gain and NF comments

 

One question Steve, regarding the transistor noise list.
Was the recently tested PZT2222A an ONSemi oder an NXP/Nexperia (PZT2222A,115) transistor?

regards
Fred
Locked updated results, transistor tests for LF noise with "half LZ1AQ" + Norton amp for 10Mc gain and NF

 

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Someone sent me some transistors to test, this is the updated results with a few more transistors added to the list. As a reminder of past tests, this tests a "half LZ1AQ" low impedance loop amp with the loop input terminated with a 2.5 uH T50-2 inductor that simulates the 39 inch diameter small loop--tested at 218 kHz for noise output. A low current Norton single transistor amp tests the transistor for gain and noise figure at 10 MHz.

Should you have a favorite transistor you think is low LF noise and/or low noise figure that's not on the list, send me one or two (preferably two) and I'll test them and update this list. Contact me privately for mailing address, ratzlaffsteve@...

Steve AA7U


 LF Noise Output 10 MHz gain, NF
2SC5551 -92 dBm +10.55 dB, 0.93 dB NF
BFU590 -93 dBm +10.48 dB, 1.02 dB NF
BFP196 -93/-92 dBm +10.51 dB, 1.07 dB NF
BFG135 NXP -92 dBm +10.42 dB, 1.07 dB NF
ZTX327 -89 dBm +10.58 dB, 1.16 dB NF
fake China 2SC5551 -89 dBm +10.50 dB, 1.19 dB NF
2SC3357 -89 dBm +10.45 dB, 1.20 dB NF
Chinese BFR96 -89 dBm +10.50 dB, 1.21 dB NF
BFR106 -90 dBm +10.51 dB, 1.23 dB NF
BFG591 -91 dBm +10.39 dB, 1.28 dB NF
PZT2222A -87 dBm +10.57 dB, 1.29 dB NF
MOT PN2222A "650" -87 dBm +10.56 dB, 1.32 dB NF
API MRF581 -88 dBm +10.49 dB, 1.34 dB NF
MOT PN2222A "329" -87 dBm +10.59 dB, 1.35 dB NF
MOT MRF517 -90 dBm +10.42 dB, 1.36 dB NF
BFQ18A -92 dBm +10.34 dB, 1.40 dB NF
CEN 2N5109 -88 dBm +10.49 dB, 1.43 dB NF
MOT 2N4401 "652" -87 dBm +10.54 dB, 1.45 dB NF
MOT MRF961 BFR96 -88 dBm +10.48 dB, 1.46 dB NF
MOT MRF571 -88 dBm +10.45 dB, 1.48 dB NF
RCA 2N3866 -88 dBm +10.45 dB, 1.48 dB NF
BFQ19 -87 dBm +10.50 dB, 1.51 dB NF
MOT MRF544 -92/-93 dBm +10.30 dB, 1.54 dB NF
CEN 2N3866 -88 dBm +10.45 dB, 1.57 dB NF
NEC 021 -87/-88 dBm +10.43 dB, 1.62 dB NF
MOT PN2222A "820" -85 dBm +10.56 dB, 1.73 dB NF
2SC5706 -86 dBm +10.13 dB, 1.85 dB NF
MOT 2N5943 -86/-87 dBm +10.44 dB, 1.91 dB NF
PN2222A "327 S-92" -82 dBm +10.53 dB, 2.33 dB NF
2N2222A "331" plastic -82 dBm +10.48 dB, 2.46 dB NF
ZTX325 -84 dBm +10.40 dB, 2.47 dB NF
KSP2222A "B24" -80 dBm +10.44 dB, 2.65 dB NF
PN2222A "H47" -80 dBm +10.44 dB, 2.72 dB NF
BFR90 -83 dBm +10.48 dB, 2.74 dB NF
PN2222A "D22" -81 dBm +10.43 dB, 2.75 dB NF
BF199 -86 dBm +10.46 dB, 2.82 dB NF
Fairchild PN2222A -81 dBm +10.48 dB, 2.93 dB NF
MPSH10 -88 dBm +10.44 dB, 3.05 dB NF
NSC PN2222A "806" -80 dBm +10.50 dB, 3.12 dB NF
metal 2N2222A "D9" -80 dBm +10.43 dB, 3.13 dB NF
metal 2N2222A "P6" -80 dBm +10.48 dB, 3.47 dB NF
2N5179 -81/-82 dBm +10.35 dB, 4.16 dB NF
metal JAN2222 -79 dBm +10.45 dB, 4.21 dB NF
PN2222A "W 72" -72 dBm +10.43 dB, 4.27 dB NF
NSC PN3563 -80 dBm +10.35 dB, 4.80 dB NF

Locked Misek/Lankford Phaser for sale

 

If anyone is interested I have a Miske/Lankford Phaser for sale that I just finished building. You can contact me at everettsharp (at) aol com for info and price.
?
The Phaser works great, you can use the same, or 2 different antennas, as long as they are 100' apart, or more. You can get up to -60dB nulls with it.
?
Everett N4CY
Locked Re: HIMARS transport

 

"Polarization" is a property of the electromagnetic wave that is transmitted, and has nothing to do with the direction your signal goes. You will have a electric field, and a magnetic field that is perpendicular to the electric field, and all that makes you your electromagnetic wave. The convention is to use?the orientation of?the electric field to determine the polarization of the wave. And even though your signal goes straight up,?the electric field is still parallel to the earth's surface, and therefore you have a horizontal polarization.

Karl Heinz - K5KHK
Locked Re: HIMARS transport

 

This has previously been discussed in detail on the Magloop IO group.

/g/MagLoop/topic/91522418#9938

Regards,

Martin
Locked Re: HIMARS transport

 

I think they are these antennas...

?
?

73 de


? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?-Manolo-
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?(EC4AA)
Locked HIMARS transport

 

Hi All,

I have noticed that the HIMARS transport vehicles used in Ukraine all have what appears to be a double loop antenna on them. Do you think that they are using a double loop that is connected in parallel to lower the antenna resistance and increase the bandwidth since the elements appear to be rather thin in tube diameter, or are they using a series connected pair of loops to lower the overall frequency of operation?? What are some of the more common HF frequencies they could be using?

--jeff
wb7aht
Locked Re: Chinese try to clone Wellbrook loop

 

I wouldn't worry.? If WW3 does happen, I'm sure most of us won't be around afterwards for the fallout.


On Thu, Sep 1, 2022 at 11:53 PM, Bob wrote:

Learn Chinese now because the way things are going you will need it in the near future.

WW3 - could be closer than you believe.

?

Bob C.

Locked Re: Interesting loop design

 

Nice link, Roger.
Strip off the book name and the root directory has a lot of stuff to look at.
<https://archive.org/download/radio-direction-finding-documents/>
Locked Re: Interesting loop design

 

The 1938 version of Keen's book available at this link...



Roger
Locked Re: Interesting loop design

 

I found the 1922 book on archive.org and the PDF is a good file.
<https://archive.org/details/DirectionAndPositionFindingByWireless>
<https://archive.org/details/directionandpos00keengoog>
<https://www.google.com/books/edition/_/u6RRAAAAMAAJ?hl=en&gbpv=1>
It looks like the source book came from the University of Wisconsin - Madison
and was scanned by the Google books project.
Locked Re: Interesting loop design

 

The 1922 edition of Keen's 'Direction and Position Finding by Wireless' is here:
Locked Interesting loop design

 

Hi Fellows ,

Where online I will find the amazing loops books for the first half of XX century?

thanks for any help!

Jorge
Locked Re: Chinese try to clone Wellbrook loop

 

As it says right there in the ebay listing, verbatim...

"Everything is tailor-made for enthusiasts who are looking for class-limited reception"

The copywriter said the quiet part out loud!


Joe AC3Y
Locked Re: Interesting loop design

 

Andrew and Geoffrey both mention Keen's books. For anyone interested in Loop Antennas Ronald Keen's books are very interesting, there are three titles but updated versions can have more data! :-
  • Direction and position finding by wireless 1922
  • Wireless direction finding and directional reception 1927
  • Wireless direction finding 1938 (revised 1947)

They all contain a lot of material which may be new to many people, some ideas long forgotten and a great deal of material? which is now called by different names.
In the 1938 edition you can find the Low Noise Vertical (before it was re- invented recently) , Twin crossed in-line loops and spaced loops ( now largely forgotten). You can also see the origins of E-Field active antennas which were used as the sense antenna ( using a valve amplifier).
The 1938 version can be found on-line. One problem is that the Ronald is miss-spelt by? ?to become? Donald, Roland and now Richard!
The last edition of 1947 included WW2 developments including Huff-Duff which was a CRT displayed automatic HF DF which played a very important role in defeating U-Boats. One of my fave tech books.

Regards, Alan G8LCO
Locked Re: how to protect PCB (loop amplifier) outdoors

 

Thank you Stephane,
Thank you Bob.

Piotr, SP2BPD
Locked Please don't use excessively long signatures

 

Those of you with insanely long signatures, please trim them.

Your signature should not be longer than your message.
--
Steve Greenfield AE7HD
Locked Re: Chinese try to clone Wellbrook loop

Bob
 

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Learn Chinese now because the way things are going you will need it in the near future.

WW3 - could be closer than you believe.


Bob C.

Locked Re: Chinese try to clone Wellbrook loop

Bob
 

开云体育

Better learn to speak Chinese, at the rate we are going you will need it in the near future.

On 9/1/2022 1:06 PM, Dexter wrote:

Now ya' got me started:

I get disgusted every time I see one of those intermodal cargo ships tie up at a US port with another load of junk.

Bob C.



On September 1, 2022, at 12:35 PM, W0LEV <davearea51a@...> wrote:
Another chest vetting:

"With Love, from China".????? Or turn it around:? "From China, with Love".

Meaning doesn't change!

Dave - W ?LEV

On Thu, Sep 1, 2022 at 11:38 AM radiojayallen <radiojayallen@...> wrote:
Thanks for verifying what we suspected. I think it's also noteworthy that the description reads like it was written by a copy person, not a technical person. Andy Ikin at Wellbrook has been constantly improving his designs over many years and offers different versions with different characteristics and it would be na?ve in the extreme for anyone to think a cheap knockoff could possibly match, let alone exceed his designs.

Just had to get that off my chest.

Jay


--
Dave - W?LEV
Just Let Darwin Work
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