PennyWhistle - Revision history

VK2NRA: redirect

2009-05-19T06:30:00Z

redirect

VK2NRA: caption, size

2009-05-12T21:56:23Z

caption, size

VK2NRA: /* PennyWhistle - 20 Watt RF Power Amplifier */ image size, captions, linking

2009-05-12T21:53:55Z

‎PennyWhistle - 20 Watt RF Power Amplifier: image size, captions, linking

KE9H: /* PennyWhistle - 20 Watt RF Power Amplifier */

2008-12-08T00:41:32Z

‎PennyWhistle - 20 Watt RF Power Amplifier

KE9H: /* PennyWhistle - 20 Watt RF Power Amplifier */

2008-12-08T00:40:37Z

‎PennyWhistle - 20 Watt RF Power Amplifier

KV0S at 22:31, 7 December 2008

2008-12-07T22:31:01Z

KV0S: 20 Watt RF Power Ampilifer

2008-12-07T22:26:14Z

20 Watt RF Power Ampilifer

New page

==PennyWhistle - 20 Watt RF Power Amplifier==

PennyWhistle is a compact RF power amplifier stage that can be used with Penelope and Alex to make a complete 16 to 20 Watt transmitter. Since any higher power HPSDR amplifier does not appear to be close in time, this amplifier can quickly and inexpensively be used to get an HPSDR on the air, either barefoot, or as a driver for a larger linear. It covers the same 160 Meter through 6 Meter bands as the rest of HPSDR.

[[Image:Pennywhistle_m1781c1a1.jpg]]

It is 10 cm by 8 cm (half Euro-board size.)

The output stage is a single stage amplifier that uses a pair of TO-220 “16 Watt” Mitsubishi RD16HFF1 parts in push pull and has approximately 19 dB gain, depending where you bias it, so it will deliver 16 to 20 watts output with ¼ watt drive.

The OZY was designed by Graham, KE9H.

The photographs and data are from the first unit I built up. Additional kits are already in the hands of Phil Harman, VK6APH, Bill Tracey KD5TFD, and Dick Faust K9IVB

I would expect this could be sold as a bare PC build-it-yourself kit. It uses surface mount, but would be easy to build. Easily wound transformers. Scotty won’t have time for more factory build boards for some time to come. As a pure kit, hopefully it could be offered in the same time frame as ALEX, and let people get on the air.

I have not thought through how to package this PA beyond this. It will fit in a Euro-Card housing, if the heat extraction problem can be addressed. We need to extract about 30 watts of heat when transmitting. Dissipation in standby is negligible. The circuit is capable of continuous duty, provided that the heatsink is big enough to hold a reasonable temperature.

[[Image:Pennywhistle_1a582518.jpg]]

PennyWhistle 16 to 20 Watt RF PA using Mitsubishi “RD16” Transistors

[[Image:Pennywhistle_m5b055a98.gif]]

Topside component layout. The two output transistors are actually mounted underneath the PC board, with their heat sink tabs bolted to the main heatsink.

The PCB is mounted to the main heatsink with ¼ inch long #4-40 spacers at four locations in the vicinity of the PA transistors. The leads from the transistors are bent upwards and through the PCB and soldered from the top. Holes in the PCB allow unbolting the transistors from the main heatsink if needed.

[[Image:Pennywhistle_m703112c0.gif]]

Top side PCB artwork

[[Image:Pennywhistle_m7a26aff6.gif]]

PCB Bottom side artwork.

[[Image:Pennywhistle_m5f4ebc1d.png]]

PennyWhistle input VSWR (without input attenuator.)

[[Image:Pennywhistle_m55aad4be.png]]

PennyWhistle Gain (dB) versus frequency

@@ Line 12: / Line 12: @@
 It will fit in a Euro-Card housing, if the heat extraction problem can be addressed. We need to extract about 30 watts of heat when transmitting.  Dissipation in standby is negligible.  The circuit is capable of continuous duty, provided that the heatsink is big enough to hold a reasonable temperature.
-[[Image:Pennywhistle_1a582518.jpg|PennyWhistle 16 to 20 Watt RF PA using Mitsubishi “RD16” Transistors ]]
+[[Image:Pennywhistle_1a582518.jpg|thumb|500px|PennyWhistle 16 to 20 Watt RF PA using Mitsubishi “RD16” Transistors ]]
 [[Image:Pennywhistle_m5b055a98.gif]]

@@ Line 9: / Line 9: @@
 The output stage is a single stage amplifier that uses a pair of TO-220 “16 Watt” Mitsubishi RD16HFF1 parts in push pull and has approximately 19 dB gain, depending where you bias it, so it will deliver 16 to 20 watts output with ¼ watt drive.
-The photographs and data are from the first Alpha-1 unit built.  Additional kits are already in the hands of Phil Harman, VK6APH, Bill Tracey KD5TFD, and Dick Faust K9IVB
+The photographs and data are from the first Alpha-1 unit built.  Additional kits are already in the hands of Phil, VK6APH; Bill, KD5TFD; and Dick K9IVB.
 I would expect this could be sold as a bare PC build-it-yourself kit.  It uses surface mount, but would be easy to build.  Easily wound transformers.  As a pure kit, hopefully it could be offered in the same time frame as ALEX, and let people get on the air.

@@ Line 1: / Line 1: @@
-[[Image:Pennywhistle_m1781c1a1.jpg|thumb|500px|PennyWistle, first Alpha-1 unit]]
+#REDIRECT [[PENNYWHISTLE]]
-'''PennyWhistle''' is a compact RF power amplifier stage that can be used with [[PENELOPE|Penelope]] and [[ALEXIARES|Alex]] to make a complete 16 to 20 Watt transmitter.  Since any higher power HPSDR amplifier does not appear to be close in time, this amplifier can quickly and inexpensively be used to get an HPSDR on the air, either barefoot, or as a driver for a larger linear.  It covers the same 160 Meter through 6 Meter bands as the rest of HPSDR.
-−
-It is 10 cm by 8 cm (half Euro-board size.)
-−
-The output stage is a single stage amplifier that uses a pair of TO-220 “16 Watt” Mitsubishi RD16HFF1 parts in push pull and has approximately 19 dB gain, depending where you bias it, so it will deliver 16 to 20 watts output with ¼ watt drive.
-−
-The photographs and data are from the first Alpha-1 unit built.  Additional kits are already in the hands of Phil, VK6APH; Bill, KD5TFD; and Dick K9IVB.
-−
-I would expect this could be sold as a bare PC build-it-yourself kit.  It uses surface mount, but would be easy to build.  Easily wound transformers.  As a pure kit, hopefully it could be offered in the same time frame as ALEX, and let people get on the air.
-−
-It will fit in a Euro-Card housing, if the heat extraction problem can be addressed. We need to extract about 30 watts of heat when transmitting.  Dissipation in standby is negligible.  The circuit is capable of continuous duty, provided that the heatsink is big enough to hold a reasonable temperature.
-−
-[[Image:Pennywhistle_1a582518.jpg|thumb|500px|PennyWhistle 16 to 20 Watt RF PA using Mitsubishi “RD16” Transistors ]]
-−
-[[Image:Pennywhistle_m5b055a98.gif]]
-−
-Topside component layout.  The two output transistors are actually mounted underneath the PC board, with their heat sink tabs bolted to the main heatsink.
-−
-The PCB is mounted to the main heatsink with ¼ inch long #4-40 spacers at four locations in the vicinity of the PA transistors.  The leads from the transistors are bent upwards and through the PCB and soldered from the top.  Holes in the PCB allow unbolting the transistors from the main heatsink if needed.
-−
-−
-[[Image:Pennywhistle_m703112c0.gif]]
-−
-Top side PCB artwork
-−
-[[Image:Pennywhistle_m7a26aff6.gif]]
-−
-PCB Bottom side artwork.
-−
-[[Image:Pennywhistle_m5f4ebc1d.png]]
-−
-PennyWhistle input VSWR (without input attenuator.)
-−
-[[Image:Pennywhistle_m55aad4be.png]]
-−
-PennyWhistle Gain (dB) versus frequency

@@ Line 3: / Line 3: @@
 PennyWhistle is a compact RF power amplifier stage that can be used with Penelope and Alex to make a complete 16 to 20 Watt transmitter.  Since any higher power HPSDR amplifier does not appear to be close in time, this amplifier can quickly and inexpensively be used to get an HPSDR on the air, either barefoot, or as a driver for a larger linear.  It covers the same 160 Meter through 6 Meter bands as the rest of HPSDR.
-[[Image:Pennywhistle_m1781c1a1.jpg]]
+[[Image:Pennywhistle_m1781c1a1.jpg|300]]
 It is 10 cm by 8 cm (half Euro-board size.)