250W Linear PA using Ampleon BLC2425M9LS250 mosfet

Latest News and Discussion about the use of the DATV transponder on Es'hail-2
G4WIM
Posts: 257
Joined: Thu Jan 29, 2015 8:36 pm

Re: 250W Linear PA using Ampleon BLC2425M9LS250 mosfet

Post by G4WIM » Wed Jul 31, 2019 7:02 am

Here's what the remote currently does

Monitoring

1. PA Vdd and over voltage limit
2. PA Idd and over current limit (high side monitoring through 0.01 ohm sense)
3. PA Temp and over temp limit
4. Provides temp compensated bias voltage
5. 500mS update rate - could be faster or slower or adaptive depending on mode of operation.

Control

1. Send command over RF link to turn on PSU into standby mode
2. Send command over RF link to turn on PA bias (effectively the PA) and activate cooling fans
3. Send commmand to turn off PA but leave fans running for 4 minutes
4. Send 12V up coax for standby mode
5. Send 24V up coax for tx mode

Notes,

1. Controls 1 - 3 over ride 4 & 5.
2. Anything over limit shuts the PA down
3. If the remote RF signal goes away for more than 4 seconds the PA shuts down but reverts to DC up the coax control
4. PA status (Vdd, Idd, Vbb, Temp, fans) are all reported remotely.
5. Each end of link uses Atmel ATmega328 as main controller plus Atmel Nano and nRF905 for the RF link plus a 4 line 20 character LCD.
6. All code is written in C so fairly easy to customize.
7. RF link freq can be 433 or 868MHz but the nRF905 modules come pre tuned for 433MHz.
8. Range is well over 100M with modest whip antenna.
9. PA will only operate if all the paramters are within limits.
10. RF link speed is 2400 baud.

If there's enough interest and someone is willing to design / produce a PCB I'll release the design and code into the wild.
I have the means to design the PCB here - but have too many other projects on the go to take care of it in the near future plus I'm having trouble with my eye sight.

Regards Tim

G4WIM
Posts: 257
Joined: Thu Jan 29, 2015 8:36 pm

Re: 250W Linear PA using Ampleon BLC2425M9LS250 mosfet

Post by G4WIM » Wed Jul 31, 2019 9:26 pm

Here's a picture of my PA controller.

If a PCB were to be created the same board could be used at both ends but populated as required.

It matches the Minitiouner Pro.
Attachments
pa_ctl.jpg
pa_ctl.jpg (218.5 KiB) Viewed 222 times

iz4ryb
Posts: 2
Joined: Wed Aug 07, 2019 3:06 pm

Re: 250W Linear PA using Ampleon BLC2425M9LS250 mosfet

Post by iz4ryb » Wed Aug 07, 2019 3:18 pm

M0SKM wrote:
Tue Jul 30, 2019 8:45 am
Yes Tim I like that idea; also a good article for CQ TV.
Currently I switch my PA with a 433MHz key fob device, a hasty solution.

Steve
Hi,
I've purchased ampleon 250w module and mounted in a Siemens case. It works fine, I'm
waiting a dish illuminator to proceed with Datv tests.
Got some trouble with internal bias compensation.
See attached picture.
Bye!
Attachments
p-Ampleon.jpg
p-Ampleon.jpg (199.61 KiB) Viewed 113 times

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