Solid State Linear Amplifier
|
* With external accessory filter unit |
The Gemini HF-1K is a solid-state 1kW 1.8MHz – 50MHz power amplifier with additional capability at 472kHz. It uses a single dual-LDMOS power device for reliability, and has an internal highly reliable low-noise switching power supply, in order to reduce the overall weight. The thermal design is very conservative with a large heatsink, and OFHC heatspreader. This, assisted by several fans and a sophisticated thermal management system, allowing the channel temperature of the LDMOS device to remain within limits which should ensure extended life, even with with heavy usage.
A major objective of the RF design has been to significantly exceed the spurious signal generation requirements of the international approvals standard (ETS 300 783 pts 1 and 2) for amateur radio equipment. To this end the Gemini HF-1K has more extensive filtering than is usual in HF PAs.
While LDMOS power FETs are amongst the most rugged RF power amplifier devices currently available, they are sensitive to RF overdrive. The Gemini HF-1K has both extensive monitoring to minimise the risk of damage by overdrive and a conservatively designed input circuit.
Following modern industrial practice, the Gemini HF kW employs full touch-screen control using a 480 x 272 pixel 108mm mm full colour TFT display. A wide range of monitoring functions can be displayed, including power output, PA drain current, VSWR, heatsink temperature, and linearity. The latter parameter provides a graphic indication of when the amplifier power output enters the region where ‘splatter’ will be generated.
As with other Linear Amp UK designs, there is no provision for ALC, as this is a major cause of bad signals.
While the control system provides for manual band selection, it will interface seamlessly with standard CAT systems. The presence of valid in-band signals is also detected and will initiate switching automatically to that band.
A high-speed, very low distortion, PIN diode, solid-state switching circuit will allow very fast full break-in operation.
A single input and three selectable antenna output connectors are provided. The latter can be preset on a band by band basis.
A 0dBm SMA feedback output is provided to allow connection to transmitters with linearisation capabilities.
The amplifier is built in a very robust all aluminium case. A modular assembly approach has been adopted with non-RF and high current DC interconnects being distributed as a single bus.
Outline specification.
Operating frequencies: 460 – 479kHz*
1.8 – 2.0MHz
3.5 – 4MHz
5.0 – 5.5MHz
7.0 – 7.3MHz
10.1 – 10.2MHz
14.0 – 14.4MHz
18.0 – 18.2MHz
21.0 – 21.5MHz
24.8 – 25.0MHz
28.0 – 29.7MHz
50.0 – 54.0MHz
*when used with an external accessory low pass filter unit
Power output: >1 kW at 1dB gain compression (200W+ on 460-479KHz)
Power input: 5, 10, 25W, 100W, customer specified
3rd order IMD distortion: better than -30dB at 1kW
11th order IMD distortion: better than -70dB at 1kW
Harmonic suppression: better than 70dB (all harmonic products)
Input VSWR: better than 1.5:1
Load VSWR tolerance: <1.5:1 for best performance with 2:1 high VSWR trip.
Note: the specifications given above should be achieved in production units, but cannot be guaranteed at this time. Linear Amp UK has spent a great deal of money on purchasing accurate high-end test equipment – which we know how to use – and does its utmost to ensure that the equipment we manufacture exceeds our claims for its performance.
See More:Link
Brief introduction for Radioddity GD-55 Plus, A Practical DMR GD-55 Plus Differentiating Factors 10W High Power IP-67 Waterproofed Mototrbo Tie... Read more
“After 20 years of maintening 9A1P at the top spots of M/S today we are back at the begining. Severe windstorm destroyed almost all antennas. We... Read more
An Oggie asks why his radio draws so much more power than the 100 watts it puts out. The answer lies in using linear final power amps in the Class A,... Read more
Yaesu Radio Co., Ltd., on April 27, 2020, introduced a network remote control system LAN unit “SCU-LAN10” that enables remote operation by... Read more
The Electromagnetic Compatibility Committee of the Radio Society of Great Britain (RSGB) still has wide-ranging questions for UK telecommunications re... Read more
Audio version Listen to an audio interview with N5UP from the RAIN Report and learn about eQSL.cc Purpose eQSL.cc is the first and only global... Read more
“A family hike up Little Mountain W7W/SK-173 and the kids took over the mic. They made eight contacts in a few short minutes. Thank you loyal ch... Read more
Table of Contents Feature enjoy the amateur radio in the apartment and operational equipment construction of Apaman Ham MLA operation of high-... Read more
I have been asked how to measure the ratios of a Balun or an Unun. So if you’re someone who has that same question this is a video for you. Read more
The US departments of Energy (DOE) and the Interior have signed an agreement making the three sites of the Manhattan Project a National Historical Sit... Read more
On Wednesday, April 27, in a notice to all VECs, the FCC again asked them to refrain from submitting any amateur radio exam session or license ap... Read more
An overview of some of the features in SDRangel, an open-source TX & RX SDR (Software Defined Radio) application. Read more
IARU was represented at the meeting of CEPT Project Team A (responsible for some aspects of the CEPT position for WRC-19), held in Prague from June 17... Read more
The EMCOMM III Portable antenna is a portable High Frequency (HF) antenna specially designed for short to long range portable and man-pack HF comm... Read more
NBTC and RAST presented the amateur radio callsign HS10A to His Majesty King Vajiralongkorn and provided equipment at a ceremony in the Dusi... Read more
Recent Posts
Radioddity GD-55 Plus UHF 400-480MHz Waterproof DMR Digital Radio,10W with 2800mAh Battery Mototrbo Dual Time Slot (Tier I&II)
Storm and high winds destroy almost everything at 9A1P
How Your Radio’s Final Amp Class Affects Efficiency
Yaesu on April 27, 2020, introduced a network remote control system LAN unit “SCU-LAN10”
RSGB Questions UK Regulator Ofcom Regarding New Interference Control Regulations
EQSL .CC – Global electronic QSL card exchange for amateur radio operators and SWLs
SOTA – Kids rule the Mic
CQ Ham Radio 2015 – April issue
Measuring Balun Ratios
Manhattan Project Sites Now Eligible for National Parks On The Air Event
FCC Not Processing New License Applications
SDRangel – TX & RX Software Defined Radio
144 and 1240 MHz bands – WRC-23 Agenda Items – Update
Chameleon EmComm III Portable End Fed Antenna Review
King Vajiralongkorn receives ham radio callsign HS10A
Warning: file_get_contents(https://plusone.google.com/_/+1/fastbutton?url=https%3A%2F%2Fqrznow.com%2Flinear-amp-gemini-hf-1k-1-8-50mhz-1kw-solid-state-linear-amplifier%2F): failed to open stream: HTTP request failed! HTTP/1.0 404 Not Found in /home/qrznow/public_html/wp-content/themes/goodnews5/framework/functions/posts_share.php on line 151
