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Help - PHSNA PCB boards required [1 Attachment]

n2apb
 

To support Dave’s recommendation for OSH Park boards, here (attached) is the RF Power Meter board we used in developing the SNA.  Worked out real nicely.

 

And you should definitely browse through all the project pcb’s they have there.  Great pcbs will help start other projects!

 

73, George N2APB

 

 

From: PHSNA@... [mailto:PHSNA@...]
Sent: Sunday, April 17, 2016 1:20 PM
To: PHSNA@...
Subject: [PHSNA] Re: Help - PHSNA PCB boards required [1 Attachment]

 

 

[Attachment(s) from ad7jt@... [PHSNA] included below]

HI All,

 

For those of you that may also be looking for a power meter board, there is another source you can consider when Jim's inventory is depleted.  Dick Faust, K9IVB, designed a small PCB for the W7ZOI power meter and made it available as an OSH Park shared public project.  The attached document from Dick's web page describes the power meter along with schematic and BOM.  It also contains links to Dick's web page and to his OSH Park shared project.  You can order three PCBs from OSH Park for about $8.00 (including U.S. shipping).  Boards are typically delivered in less than two weeks.

 

This circuit does not include the adjustable gain output amp as Jim's does.  That shouldn't be a problem when using the PHSNA controller without the analog meter.  I used Dick's board to prototype the built-in Power Meter for the Midnight SNA and had no problem feeding the AD8307 output direct to the ADC input on the SNA's dsPIC MCU.  I assume the same would work with an Adrino MCU but I have never tired it.  You can see the final implementation we used on the MSNA schematic.

 

Midnight SNA

image

Midnight SNA

NOTE (8/25/2015) ... Newly-supplied values for R2 (180), R3 (390), R15 (4.7 or 6.8), and C5 (10uF).

Preview by Yahoo

 

Note the separate power source with heavy filtering on the 5V line and minimal filtering on the power meter output.

 

 

73,

Dave Collins - AD7JT