Jan Martin Nöding
m3. RF signal-, noise and signal generators
m2. RF level meters, attenuators and dividers
m11. Grid-dipmeters and xtal testers
m12. RF power meters
m22. Old measuring instruments
c. Technical reflections (Reflecties door LA8AK)
f) Boatanchors/ Radio surplus equipment
L. VLF, MF and 136kHz equipment ideas
You'll never get all the transitions you need!
Have collected coax-connector-transitions for 30 years.
Items described on other pages:
* White noise power generator (0.5mV at 3kHz bandwidth), see page C13
* Test purpose external product detector for 50kHz-1MHz, see page C13
Power modules to amplify signal from VHF/UHF
Power amplifiers using power modules for 144 and 432MHz requiring not more than 10mW drive, see info on page d32
80m power signal generator
b) Data for
Sri, N/A now
80m Power generator using 6BQ5/EL84
It was made by LA7MI Stein Torp to test toroid ferrite cores to be used in many of his solidstate transmitter
and transceiver projects
VHF signal generator for CW/SSB tests
It was a problem to find 2m signal generator with sufficient stability for ssb/cw 25 years ago, while an RF generator was
easier to get. Here is my up-converter using SBL1/SRA1. The oscillator with 43.333Mhz xtal produces 130MHz to mix
with 14MHz from the generator, to give a signal on 144MHz. The mixer has 7dB loss. To make it easy, I added
attenuator on the input and output for total 20dB lower level than the level generator has. To convert from dBU (600 ohm
reference level, 0.775V = 0dB) to dBm (50W) you must add an attenuator of 10*log (R1/R2), where R1=600W.
And if the generator has 75ohm impedance you should use a minimum-loss-pad.
#3.4) Rohde&Schwartz SMLM VHF power signal-generator improvement
R&S SMLM (high power VHF generator) and similar instruments use high voltage regulators.......
Surplus instruments often have valve type regulators, they may last for many years, but may cause serious problem when
the smaller regulator valve passes to the Happy Hunting Grounds, the series element doesn't cause any other problems
than it is no output voltage, but the small valve causes the series element to draw full current and electrolytics and resistors
at the regulated voltage is damaged. It is several ways to avoid such problems, but the manufacturers are not concerned.
So I have nver seen any precautions. My solution is to use solid state replacement. Z20 means 20V zener diode.
Since it was done around 1985 the semiconductors may be somewhat different from what I would use today. It is a
good practice to use a cascode combination of a high current-grain transistor in series with a higher voltage device.
Had been looking for this instrument to go with
Siemens 3W518 and 3D229 for 25 years, just curious
what it looked like, now I don't have the level generator any more.... Have no documents for it.
SHF klystron type generator
HP623B The only instrument we had for 6cm when we started experiments 20 years ago. While I don't
like klystron generators, it has some other goodies inside to take care of.
noise calculation table and s/n-meters are moved
to page m23
for technical topics