4m.70MHz - PA7MU

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4m.70MHz

Projects
4m-HAM radio choices -Transmitters

Click to enlarge70 MHz 1tr FET TX by LY3LP
 

 

Click to enlarge70 MHz tunnel diode TX by LY3LP
 

 

Click to enlarge70 MHz TX by LY3LP
 

 

Click to enlarge70 MHz TX with FET PA by LY3LP
 

 

Click to enlargeSimple 70 MHz bug by LY3LP
 

 

Click to enlargeSimple 70 MHz FET TX by LY3LP
 

 


4m-HAM radio choices - Transceivers

Click to enlarge4METER (70MHz)transverter door PA5HE
Dit project is nu in aanbouw met het oog op de vrijgave van deze band.
Uitgangspunt is een 2 meter transceiver en een elektuur 50MHz transverter.

Click to enlarge70 MHz Transverter by OZ2M
This purpose of this page is to give a brief description of a 70 MHz transverter that has been published in the Danish amateur radio magazine "OZ." This way hams outside Denmark may also benefit from the design.

Click to enlargeA Simple QRP Transverter for 4m (70MHz) by G3XBM
There is almost no commercial equipment for the 4m band and certainly almost nothing from the traditional Japanese manufacturers. So, to get on the band it's necessary for me to design and build a simple transverter.


4m-HAM radio choices - Antennas

Click to enlarge70MHz 8 -EL.-50 MHz YAGI-Yagis by YU7EF
Gain 13,45 dBi, F/B 22,37dB This is also a brought-band version with very uncritical design, good pattern and great! bandwidth.


Click to enlarge70MHz 5-El.-50-Ohm-70MHz-Yagis by DK7ZB
Gain 8.64dBd, F/B 25dB This is a brought-band version with very uncritical design, good pattern and great bandwidth.


Click to enlarge70MHz Big Wheel by OE5MPL
Not drawn is the fixing point of the female N-connector and the center conductor on upper part of hub. We fixed the antenna with a 50 mm diameter aluminium pipe, which was welded onto the lower hub.

Klik voor vergroting70 MHz Yamag antenna by IK0SMG
After that I have realized the Yagi-Mag (feed slot magnetic) for the 2 m with good performance (you see iw0ffk site) I have constructed this for the 70 MHz. This is the result, simulation and real.

Click to enlarge"Hen-Tenna" for 4m by G4UNB
Having read about the "Hen-Tenna", an unusual rectangular antenna design for the high HF and low VHF bands, I wanted to try one of these on four metres.


4m HAM radio choices -Amplifiers

Click to enlarge160 W MOSFET PA by GIØGDP
This amplifier is intended to be simple in design, easy to build and as cheap as possible.
Using a SD1487, the results are typically 15 watts in and 75 out.

Click to enlargePre-amplifier for 70 MHz by G3PTU
This unit uses a dual gate MOSFET. You can use virtually any of this variety of semiconductor; the ‘Philips’ radial type e.g. BF981 appears to be just as good as the top hat types.


This is the 1st ever TEP on 70mhz (4m band) between Greece and South Africa.
His working conditions
Transceiver:YAESU FT847 modified by SV8YM (RX preamplifier CT1FFU)
Output power : 70 w
Antenna : 9el 10m boom homemade DK7ZB design at 10m above the ground

 

4meter transverter by PA5HE

see his website
language dutch!

 
 
 
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