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A Dual Band 4 element Cubical Quad Antenna

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Modelling, building and measuring a 4 element Dual Band Cubical Quad antenna (6m-4m).

Methodology adopted : 

1) Make your antenna choice according to your exeptations and your attempted utilization.
2) When done, search for what already exists.
3) Model the antennas found, then optimize them. I use for this the MMANA-GAL software (free) (download MMANA-GAL here). Chose the modelized antenna who gives your best expectations.
4) Build this antenna.
5) Install this antenna into a environnement witch is the most favourable to take your measurements.
5) Make your measurements with a correctly calibrated Vectorial Network Analyser  - Look at the official site of NanoVNA (In addition, where possible, measurements will be made in the same conditons  as those chosen for your modelling).
6) Compare your measurements with the results obtained by software modelling.
7) If needed, make physical correction to the antenna , re-modeli, re-measure until you're satisfied.

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2 Phased Verticals Array 40m

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I build last week a Bazooka vertical for the 40m (see link here) with good results.

This inspired me to build a second one and implement a two phased vertical array system.

I have chosen for a Christman phasing system : simple and easy o build

ON8IM Christman 

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Yeasu FT-DX1200 and Panadapter

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I have added a IF PanAdapter output on my FTDX-1200. The IF frequency of the FTDX-1200 is 40.455 Mhz.

To tap the IF signal, I implemented a G4HUP PAT board (Panoramic Adaptor Tap Board) : the board is to buy at  https://sdr-kits.net/Panoramic-Adaptor-Tap-Boards  . The board type is the model  PAT50M see the list here :  It is better and safer to use a PAT board, direct tapping the IF offer no protection.

I ordered the PAT board here : https://sdr-kits.net/PAT-Board-50MHz

and the mounting cables and connectors here : https://sdr-kits.net/GSIK

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1/4 Vertical bazooka antenna for the 40m

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I needed a omnidirectional antenna for the 40m.
Here is the schema of the antenna :

on8im vertical 40m

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Equaliseur UR6QW 8 bandes et Icom IC-7300

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A partir d'un article de AD5GG

UR6QW
Je me suis récement procuré un equaliseur 8 bandes de UR6QW en Ukraine. Ce processeur audio de haute qualité est fabriqué par un radio-amateur et répond aux besoins spécifiques du hobby. Son prix (120$) est extrèmement compétitif par rapport à d'autres modèles sur le marché.

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LF-MF preselector for my TS-2000 + active antenna

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The sensitivity of my TS-2000 below +/- 1500Khz dops dramaticaly.

I installed a preselector with a range from 10kHz to 600kHZ +  a PA0RDT active antenna on the RX dedicated input of the transceiver.

This dedicated RX antenna is located on the rear of the transceiver (RCA connector nr 15) and is be activated in to the menu on item 18.

 TS 2000 rear

Here is the schema

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Ameritron RCS-4 modifications

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Suite à une défectuosité du transfo d'alimentation, une grande partie des composants de mon switch d'antenne Ameritron à été détruite.

En outre des LEDS, toutes les diodes ont sauté ainsi que les relais de commutation ainsi que les électrolitiques.

 

Pas surprenant si on regarde le schéma du communtateur


 

Les modifications apportées sont les suivantes :

- Ne plus fournir de tension de commande des relais via le câble coaxial

- Eviter que ce 12V AC qui transite par ce même câble coaxial ne soit présent à l'entrée d'antenne du transceiver.

- Eviter deux polarités.

- Protéger les E/S coaxiales contre les surtensions dûes à la foudre

- Améliorer la longévité des bobines de relais

- Eviter une surtension de commande

 

RCS4 mods schematics

 

 

 

 

Preselector 10Khz-600 Khz

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I have added this simple preselector to my RX. (from LF today - RSGB publications)

Advantages : parts are easy to find  - it is easy to build - verry efficient to pick up little signal in a verry small bandpass.

Inconvenients :if you want monitoring a large bandpass with your SDR, the signals outside de BP of the filter are excluded : the best way is then to include a bypass position (use then a 6 position rotary swich), first bypass the whole preselector, pick the wanted signal , and then tune it using the other postions of the rotary switch.

 presel

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  1. Reception of DCF49 signals
  2. Weather forecast on 147 Khz
  3. WSPR signals on the 2200m band
  4. WSPR signals on 630m band

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