Search found 10 matches

Return to advanced search

Re: JUMA PA1000 Linear Amplifier

Hi to All I got lucky and bought a spool of 25 ohm silver plated RAYCHEM top quality space aviation approved cable. it is 18wag inner conductor and cable dia. is about 4.5 mm appro. it is the superb ETFE (tefzel) inner part and the outside is white cross radiation polymer ( the stuff that replaces t...
by 4z4rb
19 Jun 2012 15:09
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

Well that will be a real Monster you go dual parallel push pull or dual with combiner the 2nd option might suit better due to extremely low load lines you will need a 5 -6 ohms coax and it is very hard to work with the inner conductor is almost as thick as the outside . very hard to bend or fold. A ...
by 4z4rb
13 May 2012 19:47
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

I am happy to hear that you got the beast tamed. I have made many improvements to the board since the time you got your board BTW your board was the third i ever made so there might have been issues with it. indeed since then the output transformers had been completely reworked and redesigned using ...
by 4z4rb
12 May 2012 05:09
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

Hello David and all I have been making these modules for 8 month now and selling them either through eBay or on direct trade basis. I also make a lower power versions2x450W devices and 2x600W devices. I also implanted feedback on them and got good results and better match. also good IMD results The ...
by 4z4rb
01 Apr 2012 06:59
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

The amp SP5G is playing with was built by me .
the output trafo is a 9:1 TLT wound with a semi rigid 25 ohm coax on a 1.5"core
Looksa like he made a nice case for the amp board I supplid him
very nice project!!
Baruch 4z4rb
by 4z4rb
29 Mar 2012 17:44
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

it looks ok worth trying
by 4z4rb
03 Dec 2011 05:29
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

Hi Frank!
Indeed my experiments show it too.
great to see you
Baruch
by 4z4rb
29 Nov 2011 15:39
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

Another version of TLT output transformer with a 4;1 ratio.
wound with a 25 ohm coax by Raychem .
central conductor is 16 gauge ,loaded with ferrite with Mu=850
note the big ATC caps 0.1 uF x3000V
by 4z4rb
21 Nov 2011 20:39
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

IMG_0302.jpg
by 4z4rb
19 Nov 2011 10:46
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Re: JUMA PA1000 Linear Amplifier

Hello I have been building amps using freescale devices and NXP I am using a different LDMOS the MRF6VP11kh and the BLF578 I had problems toowith harmonic content and I have switgched to a different output matching and transformer. Instead of using the traditional Faraday transformer concept I(ferri...
by 4z4rb
18 Nov 2011 14:49
 
Forum: Juma Discussion
Topic: JUMA PA1000 Linear Amplifier
Replies: 50
Views: 98170

Return to advanced search

cron