I wanted to receive 2m with the good band panorama of my Flex6500 This offers a different experience seeing what happens on the band without tuning like a mad man..
Also at HF using split the pan adapter is very useful.
Until now used IC7100 that performs very well at 6 4 2 and 70cm but it lacks the panorama view.
I tried RTL dongle and SDR-Console but connecting the RTL dongle behind the preamp without affecting the 144 reception was not as easy as I thought. I got extra noise when connecting the 2nd receiver. Also tried N1MM with pan driver but I could not see the signals I heard it should be the other way around ? possible I did something wrong.
Tried an old DEM 144 but that is a huge box with Xtal oven and relay T/R switching.
12V 0.4A and start 1.5A to heat up
I still own 2 so called Ukrainian transverters , very small footprint 40x80x20mm nice build low priced. low standby power 30mA/12V (real)
10W from a RD15HVF1 high efficiency 12V(real) 1.5A . but spurious in band. When TX-ing 144.310 our local morning round I was reported at 145.585 clear USB signal. That was the 2nd transverter with high-level mixer ADE-12 I got from UR3LMZ. Suspect was the 58MHz xtal x 2 116MHz l.o. Calculation: 3x58=174MHz when at 144.310 174-28.31 = 145.69MHz an inband spurious that is amplified by the PA..
Another known issue with this XVTR type is self oscillating 2m and 4m too.
Self oscillating started as soon as the tranverter was top covered. It works fine on the bench,but when closing the K3 top cover it starts to oscillate. This XVTR is perfect fitting in a K3.
I was advised to apply a resistor over the driver L. But shielding the PA output circuit as in the picture above stopped the self oscillations. Tx gain is than not reduced, still 10W 12V(real). (sometimes 12V means 14V)
Used it with an eBay 116MHz Rojon but the signal at 116 was not clean enough possible a good 116 or 114 tcxo would be oké The other XVTR with dual-gate mosfet mixer is stil in my K3 I can not use it now because of this 58MHz x-tal.
This XVTR was in my drawer for several years but now given a second chance by
switching off the onboard 58MHz X-tal oscillator ( oscillator base jumper to ground) and drive direct 114MHz to the ADE-12 mixer.
A GPS disciplined signal generator of Leo Bodnar is used, this can be set between 400Hz to 810 MHz with its USB configure program. The signal is very clean. The XVTR is build in a small box 8x10.5x 2.5 cm Alu also heath-sink it drives 3-4 to the input attenuator of my BLF188xr PA.
No extra cooling needs at that level. This box was left over from an 10-15W wide band PA also using the Mitsubishi RD15HVF power mosfet
About the used housing, I can not find where to buy this size and type housing.
Al I find is too big big heavy Eddystone types with the edges internal reducing the internal space.
Not the simple nice profiled 2 u shaped top and bottom part hold together with front and back plates.
I have overdrive protection in my PA Arduino controller for safety.
In the flex it is easy to ad an 144MHz XVTR using 30-32 MHz as i.f.
The reports I got so far are good it is a pleasure to work the bands enjoying the help of panorama view.
Next will be the checking with a spectrum analyser.
whole 144 to 146 the span can be tailored smaller or wider PI7HVN local beacon can be seen at 144.422 quite al lot of signals low in the CW part I have here must be local QRM from PC or other equipment but no faint carriers in the Flex pan view they arr real signals I have to find the source of.
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