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NXP Homebrew RF Design Contest

John Scherer
 

Just came across a bit of news the might be of value to the bitx community.  It seems that on May16th, NXP launched homebrew RF power amplifier design contest, utilizing their newMRF1-1AN or the MRF300AN transistors.  1st place is $3K plus $1k in NXP product.  It onlyt goes on until November 14th 2019 so times-a-waistin ;-)
--
John - N0CTL

jk.futter@...
 

I entered this contest way back in June
Circuit diagram is done for 160m -2m 200 watt PEP 12 volt mobile amp suitable for ubitx ft817 ft818 ic705 etc
still to actually make the amp module but have the ferrites etc for the in / out circuits

w8fgqrp
 

That amp project is exactly something I would love to have in my Shack!  
Love to hear more on this! 

On Friday, September 27, 2019, 3:01 PM, jk.futter@... wrote:

I entered this contest way back in June
Circuit diagram is done for 160m -2m 200 watt PEP 12 volt mobile amp suitable for ubitx ft817 ft818 ic705 etc
still to actually make the amp module but have the ferrites etc for the in / out circuits

barry halterman
 

That amp would be of great interest as the mrf101an seems very robust in HF application.
They are not too expensive either!

On Fri, Sep 27, 2019, 3:33 PM w8fgqrp via Groups.Io <w8fgqrp=yahoo.com@groups.io> wrote:
That amp project is exactly something I would love to have in my Shack!  
Love to hear more on this! 

73 de Seth - W8FG 


Sent from Yahoo Mail for iPad

On Friday, September 27, 2019, 3:01 PM, jk.futter@... wrote:

I entered this contest way back in June
Circuit diagram is done for 160m -2m 200 watt PEP 12 volt mobile amp suitable for ubitx ft817 ft818 ic705 etc
still to actually make the amp module but have the ferrites etc for the in / out circuits

Razvan (M0HZH)
 

Today is the last day of the challenge. I sent an entry as well,  "A 600W broadband HF amplifier using two US$35 LDMOS devices"

Video: https://www.youtube.com/watch?v=YDm3PJY7yxk

Article with more details: https://qrpblog.com/2019/10/a-600w-broadband-hf-amplifier-using-affordable-ldmos-devices/

Cheers,
Razvan (M0HZH)

 

Looks good Razvan, all the best!

Raj, vu2zap


At 31-10-19, you wrote:
Today is the last day of the challenge. I sent an entry as well,  "A 600W broadband HF amplifier using two US$35 LDMOS devices"

Video: https://www.youtube.com/watch?v=YDm3PJY7yxk

Article with more details: https://qrpblog.com/2019/10/a-600w-broadband-hf-amplifier-using-affordable-ldmos-devices/

Cheers,
Razvan (M0HZH)

Tony W
 

I'd not seen this contest, which looks a great idea.  
Razan,  I'm looking for a med power HF amplifier to build, and have been thinking of MRF150 or similar (i have a couple of used ones).  However it is now quite an old design, and a  250W amp was published in several issues of the ARRL Handbook. I've seen more recent designs using quite costly devices - however good they are the cost puts me off.
If your design is repeatable I'm interested.  Good luck in the design contest. 

Best 73s
Tony, G4CIZ

Vince Vielhaber
 

Nice write up. I'm looking forward to either boards or kits for this.

Vince - K8ZW.

On 10/31/2019 07:25 AM, Razvan (M0HZH) wrote:
Today is the last day of the challenge. I sent an entry as well, "A
600W broadband HF amplifier using two US$35 LDMOS devices"

Video: https://www.youtube.com/watch?v=YDm3PJY7yxk

Article with more details:
https://qrpblog.com/2019/10/a-600w-broadband-hf-amplifier-using-affordable-ldmos-devices/

Cheers,
Razvan (M0HZH)

 

Very cool! Great work
--
David

 N8DAH
Kit-Projects.com

Shop is open!

ajparent1/KB1GMX <kb1gmx@...>
 

Currently building up an amp for 2M use using BLF184 a 600W device.
Since the basic amp is a mod to a dead TV transmitter amp the board
and many parts on it are free.

$137  For a BLF184  (no epay, fakes)
     0     Heatsink 7x10x2" from current supply 
            FYI the nearest part was 37$ and is smaller
            Has to remove in the range of 300-400W of heat
$ 34    Copper heat spreader 25x3x12inches 
$ 75    SWR and low pass filter for 2M W6PQL
$ 80    Amp control board
$ 10    bias control board, temp compensated.
$ 79    50V 20A [1000W] switch mode power supply
$150    box with metering to package it is an unknown budgeted $150.
$  25    used, TR relay, High isolation SMA for input side
$  20    board for Omron G2 series for output 
$  10    MPJA  two fans for cooling.

That list does not include misc SMA cables and other cables as needed (Fyi: all PTFE)
Or the 15A rated IEC input connector with filter (on hand) as well as my time to do the
mechanical and electrical work.  Likely a few $$ on screws, spacers, misc hardware.

Its about the price of the transistors.  It is nearly the cheap part even if free the rest
of the REQUIRED items to complete the amp are not cheap and those are low cost.

Another example on the bench:
$15  EBAY 70W HF amp... GIven to me, module kit
        The person that gave it to me wanted to know, is it real or junk?
$   5  two sets of IRF530 spares (suggested on many sites as must have)
$ 13  heatsink MPJA or Amazon
$ 70  Low pass filter  multiband 100W (w6pql board and 10 OmronG2 relays)
         I want this for a later much higher power project so, no junk.
         Closest epay is 47$, looks in adequate.
$   5  Input attenuator to keep the Ft817 (or other 5W radio) from over driving it
$   5  fan 
$  22  LMB box or similar box
It is assumed it runs on nominal 12V (at 15A peak a 12V 7ah gell cell is too small).
The board kit is cheap but far from a complete and well constructed AMP.

Things I actually do on my bench as a sample of real cost of building an amp.

Allison

Razvan (M0HZH)
 

I made some improvements to the design and I am preparing to make a small limited run for the kit in the next few weeks. I will post future updates on this page, where you can also sign up to be notified via email:

https://qrpblog.com/a600-hf-6m-600w-ldmos-amplifier/

Jack, W8TEE
 

Did I miss what the kit will sell for?


Jack, W8TEE

On Monday, November 4, 2019, 10:40:47 AM EST, Razvan (M0HZH) <razvanfatu@...> wrote:


I made some improvements to the design and I am preparing to make a small limited run for the kit in the next few weeks. I will post future updates on this page, where you can also sign up to be notified via email:

https://qrpblog.com/a600-hf-6m-600w-ldmos-amplifier/

--
Jack, W8TEE

Razvan (M0HZH)
 

Hi Jack,

I'm still working out the price, it should be quite competitive.

Razvan.

Jack, W8TEE
 

Thanks...I'll keep watching!

Jack, W8TEE

On Tuesday, November 5, 2019, 9:17:46 AM EST, Razvan (M0HZH) <razvanfatu@...> wrote:


Hi Jack,

I'm still working out the price, it should be quite competitive.

Razvan.

--
Jack, W8TEE

Dennis Beverage
 

Put me in line for one of these kits.  This amp, coupled with a Bitx radio, could possibly turn out to be the biggest contribution to qrp amateurs since superhet receivers.  (I doubt 600 watts qualifies as qrp though. And a 48 volt power supply might be a bit of a lug for SOTA operators.).  Still would make a Bitx a lot of fun in the shack.

But Oh, I love the trials and tribulations of kit building.
--
Sodypop🤠
KJ6VGB

ajparent1/KB1GMX <kb1gmx@...>
 

Will it be complete with low pass filters, TR switching and
any other protection circuits?  

At 600W (out?) it will want a 800-1000W power supply.

Looks like fun.

Allison

Gordon Gibby
 

Allyson this might be a chance for you to step up with those designs for the low pass filter


On Nov 5, 2019, at 14:59, ajparent1/KB1GMX <kb1gmx@...> wrote:

Will it be complete with low pass filters, TR switching and
any other protection circuits?  

At 600W (out?) it will want a 800-1000W power supply.

Looks like fun.

Allison

ajparent1/KB1GMX <kb1gmx@...>
 

Being retired means I don't fund loosing projects.
https://www.w6pql.com/a_1.5kw_lpf_for_160-6m.htm

He makes them and they are stout enough to take 600W.

Allison

Razvan (M0HZH)
 

Dennis, if you could sign up for email notifications here, I'll let you know when the first batch will be available:

https://qrpblog.com/a600-hf-6m-600w-ldmos-amplifier/

Allison, at the moment it will be just the PA unit as seen in the article / video, with some improvements. I am working on developing all the other necessary components (monitoring & protection, switching, filtering etc) but as you probably know these things take time. In the mean time, I will make available all the necessary documentation.

Cheers,
Razvan (M0HZH)