Sitemap | 中文版
HomeAbout usProductApplication CasesQuality ControlPlace an OrderDownloadContact us
TINMAN AMP uses HG 2SC2879
HG 2SC2904 Used in IC725
HG MRF477 Feedback From USA User
HG FA641TB applied in Long March III Carrier Rocket
HG MRF477 used in 40W HF amplifier
HG FA431 applied in aerial refueling
HG 2SC1969,2N3866 application feedback
HG MRF466 is applied in single sideband radio
HG 2SC1971,2SC1972,2SC2539, 2SC3022 feedback
HG MRF317 applied in national design contest
Part Number:

RF Power Transistors
2SC Series
2N/3DA/3DG/3DK Series
PT/PTB/SD Series
Other Series
RF Power Transistors Package
Screw Cooling Structure
Flat Cooling Structure
Ceramic Cooling Structure
Application Cases HomeApplication Cases
HG MRF477 used in 40W HF amplifier

Author: Wuhan Zheng

The following comes from real customer feedback, without making any modification. You can visit the following web site to verify. If you are interested in HG MRF477, you may contact us. We can coordinate with the article's author to provide you with the application guidance.

●  The article source 
●  HG produce MRF477  
We use HG product MRF477 to make 40W shortwave amplifier
●  Transistor Performance
1-30M, third-order intermodulation reach 30dB
●  Machine performance
Meet the export standards of the United States
●  Reliability
Output reaches 100W using two HG MRF477, current now reaches 15A.The temperature of cooler is about 70 degrees. Many of our Friends are also surprised by the experiment and shocked by the TO-220 packaged product, reaching 100W.
●  Debugging process
Draw PCB two times. Our Friends highly think of this PA.

PCB Real Photo


80 meters of output spectrum

40 meters of output spectrum

【20 meters of output spectrum

【15meters of output spectrum

【10meters of output spectrum

20 meters of intermodulation testing

10 meters of intermodulation testing

Understanding problems:
1. Third harmonic is high: This form of push-pull amplifier circuit is almost the same as three real multipliers, with the only difference in working point. Transistor multiplier is needed to be set to C class according to the requirement of three frequency multiplier. Refer to ARRL Handbook 2008, Page 14.52
2. On the harmonic and IMD optimization, please refer to
3. On transformer and related compensation, please refer to Philips Application note EC6907/EC7213

HG Semiconductor Co., Ltd. Copyright 2016. All Rights Reserved. ICP number: 11030609
Address:6th Floor, 20# Building, 53 Xiuxi Rd, Binhu District, Wuxi, Jiangsu, China; Postcode: 214122
Tel: +86-510-81023902 +86-755-61285520  Fax:+86-510-81023909