RADIODAN W7RF
My
Henry 3K Classic X MKII
3CX1200A7 Rugged, conservative POWER!
OK, I'll admit I just MAY be a little bit biased, but I really think my
Henry 3K Classic X MKII is the best amplifier I have ever owned (and I've had quite a few
including Alpha 78, Alpha 87A, Heath SB-220, SB200, HA-14, Yaesu FT2000B, Hallicrafters
HT-45, homebrew 813's, homebrew 3-500Zs, and an early Henry 2K). Nothing puts out the
power with <100 watts of drive as effortlessly as my 3K Classic X MKII. Even in the low
voltage CW position it easily does the legal limit of 1500 watts output.
No "toy tubes", a real rugged 3CX1200A7. No "computer type"
capacitors, you get a real transmitting type oil filled HV capacitor with a resonated
filter choke. COMPARE the quality!
HENRY has no equal!
Can you operate RTTY (contesting too!) with your amp at the legal limit? Henry
can!
Here's some pictures of my unit. They are all thumbnails so the page loads faster. Just
click on any of them for a larger picture.
Radiodan now has a 3K Premier console (same as the 3K Classic X
MKII but adds 160M and vacuum output relay for QSK)
![]() In the W7RF shack Prowling for DX! |
![]() Busy makin' power! |
![]() The W7RF antenna farm |
RADIODAN W7RF antennas Open wire fed 170' invee @ 70' Force12 C4XL @ 72' M2 6M5 6M beam @ 76" M2 440-11 yagi @ 77' Force 12 30M dipole @ 80" M2 2M12 2M beam @ 82" VHf/UHF verticals @ 85' Not up yet, Create CD78 80/75M rotatable dipole |
![]() What, no HENRY? |
![]() An easy 1500 watts while testing BIRD elements |
All Henry HF amps are instant on, ready NOW! RTTY contesting is the toughest mode and Henry does it easily! |
Radiodan homepage: http://radiodan.com/ RF Power page: http://radiodan.com/rfpower.htm Ham Stuff page: http://radiodan.com/hamindex.htm |
![]() Rear view |
![]() Blower, oil filled HV capacitor Look at this construction! |
![]() Step start relay (left) Step start resistor (middle) |
Some manufacturers won't give the schematics to their
amplifier even after you buy it. Why not? Henry gives a complete manual WITH schematics. |
![]() Blower keeps the tube COOL |
![]() Bottom RF deck view showing clean construction |
![]() Massive choke (left) 4400 volt transformer (rt) |
I have not seen any currently produced Amplifiers for amateur radio that use a Choke input HV filter and oil filled capacitor but HENRY! |
![]() The clean RF deck Notice the lack of jammed in parts. |
![]() Henry makes the roller inductor and plate choke in their LA facility |
![]() Showing input circuit. Yep, Henry makes all that too. |
We make our own bandswitches, roller inductors, plate chokes, filament chokes, tube sockets, chimneys, coils, input matching networks, high voltage switches, all metal work and cabinetry. |
![]() Complete view, bottom of RF deck |
![]() RF deck showing tube and teflon chimney |
![]() How we keep it all in sync |
All this in a 1 year warranty and using the most rugged
tubes in our designs. Built HENRY tough! |
| Henry RF Power | Makes it tough to look at anything else, eh? | Henry HF pricing | |
|
Radiodan's 3K Premier (3CX1200A7) settings, (90-100 watts drive) |
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| Frequency | Tune | Load | Plate current | Grid current | Power output | Notes |
| 1830 | +19 | 188 | 780 | 200 | 1700 | |
| 1885 | +7 | 194 | 780 | 210 | 1700 | |
| 3515 | 139 | +7 | 750 | 180 | 1700 | |
| 3800 | 120 | +8 | 760 | 200 | 1850 | |
| 3870 | 117 | +4 | 760 | 200 | 1850 | |
| 3950 | 113 | +4 | 760 | 200 | 1850 | |
| 7020 | 73 | 162 | 720 | 220 | 1800 | |
| 7185 | 72 | 104 | 750 | 230 | 1900 | |
| 7250 | 71 | 104 | 750 | 230 | 1900 | |
| 14020 | 49 | 119 | 750 | 260 | 2050 | |
| 14210 | 50 | 133 | 780 | 210 | 2000 | |
| 18125 | 35 | 124 | 800 | 200 | 1750 | band sw on 15M |
| 21020 | 26 | 120 | 780 | 280 | 2200 | |
| 21300 | 25 | 135 | 780 | 260 | 2000 | |
| 24925 | 18 | 126 | 840 | 200 | 1650 | band sw on 10M |
| 28020 | 13 | 130 | 830 | 210 | 2050 | |
| 28400 | 12 | 70 | 820 | 230 | 1950 | |
| As you can see from
grid current readings, the tube is NOT yet saturated and the power supply
has plenty of reserve. These reading were taken into a BIRD 50 ohm load. We recommend operating at the legal limit. The Henry has a SAFE operating margin even at full legal power in RTTY/PSK 31 or other continuous duty modes. These are MY readings, yours MAY vary. However, if you need a place to start, you may use these settings and start to tune your amp with 10-20 watts of drive to determine YOUR settings. |
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