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HF-Index of pa0nhc technical HAM pages.

Since 20150113 this site is located at: http://www.pa0nhc.nl/ 
© The use, copy and modification of all info on this site is only permitted for non-commercial purposes,
and thereby explicitly mentioning my radio amateur call sign "PA0NHC" as the original writer / designer / photographer / publisher.

PCBs can be ordered at :
If a link does mot work, the page was updated by me. REMEDY :  Press F5 and try again.

EN = Read this article in English language     NL = Lees dit artikel in Nederlands

EN

                              (This article is still under construction)
      80m band MAGNETIC receiving antenna.
- Antenna directive pattern is like a full size dipole on low height.
- If rotate able, local noise sources can be "nulled".
- Much smaller size and more signal than an RX loop antenna.
- Very good sensitivity and selectivity due to optimal Hi-Q ferrite
   antenna and Hi-Z FET buffer input.
- Effective NVIS antenna between 1.8 and 7.2 MHz.
- Tuning range is 3.5 - 3.8 MHz.
- Tuning range is adaptable for between 0.1 and 21 MHz.
- The tuning-"span" is adjustable.
- Including internal noiseless power supply.
- Acts like a very selective pre-selector.
- Very good strong signal handling due to back-to-back varicaps. 
- Standard available components.

                        Special, developed by pa0nhc.
- One thin coax line transports :

  
1. The DC power towards the antenna unit  +
   2. The DC tuning voltage towards the antenna unit  +
   3. The received RF signal towards the tuner unit and the RX.

The fully new designed PCBs will become available on request.
Info at :


                                  Antenna unit

                                         Tuner unit with build-in noise less power supply.
EN

28 - 435 MHz directional couplers
on a small piece of PCB,
in a cheap metal enclosure.
For factory made PCBs ask info at :

Updated : 20180103


New design for coupler with DC output
on factory made double sided PCB.

EN

Radically new designed :
Top quality 80m ARDF direction finding receiver, single super 10.7MHz IF.

All info now in easy printable PDF files.

With build-in high-Q BALANCED ferrite antenna,
BALANCED Jfet buffer stage and
BALANCED IC mixer.

Very sensitive. Gain adjustment range >= 90 dB.
Very positive sense action.
Small and light (305 g). Pwr : 16-26 mA @ 9V-6V.
Constructed with cheap ABS housing,
commonly available modern components, and
Ready wound Neosid coils.
Only 4 SMD components.

All detailed building info in easy printable PDF files.

Order professional double sided PCBs at

Last update : 20171216

See also the
2m version.


Finished receiver on factory made PCB (100+ components).
The version above uses a 17cm rubber whip as sense antenna.
The version below uses a piece of ALU pipe on top as sense antenna. 

   

EN

Adjustment-free active
RF rms low power meter.
Measuring 4uW to 4mW.
-55 dBm to +6 dBm.
Internal 50 Ohms load.
32kHz - 800MHz (2.5Ghz).
2 ranges : FSD = -14 and +6 dBm.
Optimal double sided SHF PCB design.
(Battery) powered 4 - 5V, 3 - 8mA.
Standard ABS housing 9 x 9 x 6 cm3.
dBm scale and switch scale drawings available.
All detailed building info in easy printable PDF files.
pa0nhc 20170922 / 20171218
Order a SHF designed PCB at :  .

EN

Adjustment-free active thru-line
RF rms power meter
(for external 50 ohms load).
Measuring 0.4mW - 200W.
3 ranges : FSD = 0.02 / 2 / 200W or -8 dBm to +53 dBm.
dBm scale and switch panel drawings available.
16 kHz - 30MHz.
(Battery) powered 4 - 5V , 3 - 8mA (30 hrs).
Standard cheap ABS housing 9 x 9 x 6 cm3.
All detailed building info in easy printable PDF files.
Specially shaped RF-PCB fitting a cheap ABS box available.

pa0nhc 20171222


Without any adjustment, immediately correct +50 dBm indication
with 100W RF from a TS570D.

EN

Tune your magnetic loop antenna for maximal radiation.
Magnetic near field strength indicator for
"Magnetic loop antennas".

With roof top sensor unit and meter unit near the TRX.
Two sensitivity ranges.
Battery operated.
All detailed building info in easy printable PDF files.
20171221


Meter and antenna units.

EN

NL

Easy and fast VSWR plots of antennas and filters on a laptop.
Complete with all software.

New version PCB#75 can be ordered  at :

- cheaper BNC chassis bus
- 6 lead SOT-23 ic's for easier soldering
- 35mil holes for easier fit of both boards into the main board.
20170621. 
Makkelijk en snel VSWR grafieken van antennes en filters op een laptop.
Inclusief alle software.

Nieuwe versie PCB#75 is beschikbaar.
- Goedkopere BNC behuizing bus
- makkelijker te solderen 6 pin SOT-23 ICs
- 35mil gaten voor makklijker plaatsen van de boards

EN

Active E-field
wideband DX receiving antenna.
! No IMD, clean reception !
REM:
A from Oekraïne available commercial SMD variant is a copy of an older version .
Not approved by me.

Please support my work by ordering PCBs from me.

20170828 / 20171219
Schematics again improved by me.
 
Two "Japanese" S-points higher sensitivity.
Max. output 2Vrms (S9+92dB !).
Output IP3 (7+8 MHz) : +35 dBm
IP2 : +45 dBm
Fused splitter.
Range ca. 50kHz to 30MHz.
Fully class A circuitry.

Order new double sided PCBs at :


Completed Miniwhip version 13, fused, with optimal setup of T1
and new type UHF driver T2.

EN

NL

Simple noise free power supply.
Perfect suitable for the Miniwhip antenna.
The PCB fits into a standard 
9x16 cm2 Hammond ABS box.
   

230V~in, 12V/125mAdc out.
A professional double sided PCBs is available.

Last update : 2017
1018 
Het professione printje is beschikbaar.
Eenvoudig stoor vrij voedinkje.
Zeer geschikt voor de Miniwhip antenne.
De print past in een standaard
 9x16 cm2 Hammond ABS doosje.

EN

NL

All weather outdoor magnetic loop antenna for transmitting on 40-(60)-80m
with optimal cost / performance ratio.

>> Perfect broadband transformer matching <<.
New 40m+80m matching transformer-set, remotely switch able.
NO TVI / BCI
35mm copper water pipe radiator for max efficiency on 80m.
THICKER IS MORE EXPENSIVE, BUT NOT BETTER !


20170614

Weerbestendig magnetisch zend raam voor 40-(60)-80m
met optimale prijs/prestatie verhouding.
>> Perfecte breedband transformator aanpassing <<
Nieuwe, op afstand omschakelbare, 40m+80m transformator combinatie.
GEEN BCI / TVI
35mm dikke straler van  koperen waterleiding buis met maximaal rendement op 80m.
DIKKER IS DUURDER, MAAR NIET BETER, DUS ZINLOOS !


New 40/80m matching transformers PCB available.

NL

EN

Antenna SWRsweeper V1
re-editted 20170404
 With diode-compensating buffer stages

With mask for DIY PCB

Easy and fast SWR plots of antennas and filters on a laptop.


SWR curve of my 10m circumference loop.
Sweeper connected at the transmitter end of the coax.

NL

Voorkom dat lichtnet storing uw radios bereikt :

Net storing filter (23,52 Euro) ?
of
"Ultra isolation transformer" (>= $ 835) ? 

EN

NL
Finding radio-noise-sources using a special wideband AM receiver "EMV-spy".

Radio storing bronnen zoeken met een "EMV-spion".
NL The ongoing experiment : 600W PA with BLF188XR. It takes so long because lack of funds HIHI.
EN


VERY SPECIAL ====>>

Impossible ? Another "wonder antenna" ?
Check it out !

The "pa0nhc Cobra" symmetrical wire antenna (3.5-14MHz).
Symmetrical dipole feeded with coax at one end

This could be THE solution if you want a symmetrical antenna, but you cannot connect a feeder to the center of a antenna.

Minimal induced RF in mains wiring, speaker cables, telephone line => No TVI / BCI !!!!
Low received noise level.
No transformer, just one dedicated coax choke.
Matches to 50 Ohms on lowest band (making strong NVIS signals).
Needs asymmetrical tuner on higher bands.

EN

NL

Xfilt DEMO

Xfilt : Filter voor lokale HF storingen.
Incl. aktief storing antennetje.

Xfilt : Noise canceling RF filter for locally generated noises.
Including active noise antenna.

EN

NL

The grounding and de-noising
of my antenna system.

20160526

De aarding en ontstoring van
mijn antenne installatie.

EN

NL

- Improved automatic tuner for loop antenna.
Pure analog (Without software).

- Verbeterde automatische tuner voor een raam antenne.
Puur analoog (zonder software).

EN

NL

De-noised 12V PC SMPS. 
Cheap 12.1V / 35A power supply for 100/200W transceivers.

Goedkope 12.1V / 35A voeding voor 100/200W zendontvangers .
Een ontstoorde 12V PC voeding.

EN

NL

De-noising a common used scoot mobile charger.

Ontstoren van een algemeen gebruikte scootmobiel lader.

NL

EN

Ferrite transformer experiments.

EN

NL

- Simple adjustable DC tune-motor driver.

- Eenvoudige regelbare DC afstem motor besturing.

EN

2 Watts 80m CW or AM transmitter for ARDF.
2W CW into 50 Ohms load.
0.5W AM when externally modulated into 50 Ohms load.
Sturdy, withstands very high SWR.
Fixed accurate frequency without adjustments.
Unconditionaly stable and sturdy.

Special designed single sided PCB for good performance and good efficiency.
Resulting in a well filtered signal, no parasitics,
 
If using a 50 Ohms antenna, quick setup in the field without further adjustments.

2013

EN

80m 65mW AM foxoring transmitter.
Including adjustable modulation tone.
Well filtered, clean signal.
No adjustments with 50 ohms antenna.
20130505

EN

80m beeper
(mini-TX "Sputnik").
Single frequency, simple, stable, clean signal.
CW keyed.
Well filtered, clean signal.
No adjustments.
201305