[Moon-Net] RF FET selection for 432 MHZ SSPA

Edward R Cole kl7uw at acsalaska.net
Wed Nov 30 19:40:20 CET 2016


I've built Jim's 150w 1296 LDMOS amp and have a 
second one to finish this winter.  Recently I was 
offered a 300w Mirage for $350 but decided 
against it as I realized the 1200w W6PQL 2m RF 
pallet kit was only $480 and that could replace my 8877 (someday).

Having 300-500w for 2m-SSB would make my NC 
duties easier as that would ensure a signal any 
20w station with a "coat hanger" antenna would 
receive 100km north in Anchorage.  Running full 
power would equal what I run on eme with the 8877 
driven with RFC 3-317 (loafing at 55w).  The 
1200w sspa could be located at base of the tower 
cutting a lot of transmission line loss (maybe 
half my 1.7 dB and only require running LMR-400).

So my question is how much output do you run on 
JT65?  Can you comfortably do1200w or what?

I am planning to build the kit but have the LDMOS 
installed by Jim on the cu heat spreader and buy 
the pre-milled heatsink as I would have to pay for that in any case.

I might build a dual amp for full 1500w with each module run at 750w.

73, Ed - KL7UW
be nice to rid the shack of all that heat and blower noise

At 08:46 AM 11/30/2016, Ken Arck wrote:
>My results on 6 & 2, using Jim's building blocks 
>(The 2 meter one is used for  JT65B EME and goes 
>for hours and hours of use this way)
>At 09:34 AM 11/30/2016, Ed K9EK wrote:
>>Look at "w6pql.com" or "rfham.com", (although 
>>something may be wrong with the latter; my 
>>anti-virus says it is compromised). These 432 
>>pallet amplifiers (for 50, 144 1nd 432 MHz) use 
>>the MRFE6VP5600H dual LDMOS transistor. On 432, 
>>4W in gets 500W out. Run on 48VDC. Fairly easy 
>>to build and very tough and reliable. I've 
>>built all 3; 50 MHz gets 600W out with 1W in, 
>>144 MHz gets 500W out for 1W in (this is the 
>>easiest version to build). Awesome stuff. I've 
>>written several papers on them if you would 
>>like to see them. There are also 1+KW versions. 
>>These were first shown in DUBUS 4/2012.
>>Ed K9EK
>>From: "Rick Muller" <rick.muller at asml.com>
>>To: "moon-net" <moon-net at mailman.pe1itr.com>
>>Sent: Wednesday, November 30, 2016 11:58:29 AM
>>Subject: [Moon-Net] RF FET selection for 432 MHZ SSPA
>>Busy here building a SSPA for 432 Mhz
>>Currently using a MRF 186 ..  with 8 watt RF in 
>>I get about 90 Watt out .. using 26 Volt supply
>>I could replace the MRF 186 with another RF FET 
>>, my power supply can deliver up to 48 Volt 
>>with 25 Amp and the heat sink is big .
>>I am not an “ advanced “ RF builder so I do 
>>not know which FET to select .. there are new ones on the market every week ..
>>But changing the FET could also mean changing 
>>the design .. what kind of parameters are 
>>critical if you replace one type FET with the other ??
>>73’s Rick, PA1BVM
>>-- The information contained in this 
>>communication and any attachments is 
>>confidential and may be privileged, and is for 
>>the sole use of the intended recipient(s). Any 
>>unauthorized review, use, disclosure or 
>>distribution is prohibited. Unless explicitly 
>>stated otherwise in the body of this 
>>communication or the attachment thereto (if 
>>any), the information is provided on an AS-IS 
>>basis without any express or implied warranties 
>>or liabilities. To the extent you are relying 
>>on this information, you are doing so at your 
>>own risk. If you are not the intended 
>>recipient, please notify the sender immediately 
>>by replying to this message and destroy all 
>>copies of this message and any attachments. The 
>>sender nor the company/group of companies he or 
>>she represents shall be liable for the proper 
>>and complete transmission of the information 
>>contained in this communication, or for any delay in its receipt.
>>Moon-Net posting and subscription instructions 
>>are at http://www.nlsa.com/nets/moon-net-help.html
>>Moon-Net posting and subscription instructions 
>>are at http://www.nlsa.com/nets/moon-net-help.html
>President and CTO - Arcom Communications
>Makers of repeater controllers and accessories.
>Authorized Dealers for Kenwood and Telewave and
>we offer complete repeater packages!
>AH6LE/R - IRLP Node 3000
>"We don't just make 'em. We use 'em!"
>Moon-Net posting and subscription instructions 
>are at http://www.nlsa.com/nets/moon-net-help.html

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.pe1itr.com/pipermail/moon-net/attachments/20161130/0cdd26a2/attachment.html 

More information about the Moon-net mailing list