QRZ.COM
ad: wmr-top
Please login help/register callsign: password: secure login
Database News Forums Swapmeet Resources Contact
 12:14:29 UTC 30 Aug 2014 
Advanced Search Current Hot Callsigns XML Logbook Data QSL ListMaker Database Downloads DX Spotting Network Ham Club Database QSL Corner Top Web Contacts Expired Callsigns QRZ's 1993 FCC Database Daily Update Reports Just Added Callsigns Database Help Forum
Amateur Radio News General Announcements Special Events, Contests, etc. Hamfests and Conventions Silent Keys Headlines
Forums Home Discussions, Editorials, Talk Technical Forums Logging and Contesting RV and Mobile Help Forums
Ham Radio Gear for Sale Ham Made Gear General Merchandise Swapmeet Hot List Ham to Ham References Stolen Radios, Scams and Rip-offs
Site Menu... Practice Amateur Radio Exams Amateur Radio Study Guides Online License Renewals License Wall Certificates Commercial Ham Radio Links DX Country Atlas Grid Mapper Ham Radio Trivia Quiz Life Member Honor Roll
Help Desk, for accounts, lost passwords, etc. Add your callsign to QRZ Subscription Services Users Help Forum Frequently Asked Questions - FAQ QRZ en Espanol Privacy Statement Advertise with QRZ List of Current Advertisers About QRZ Donate to QRZ Contact us
ad: L-HROutlet
ad: l-assoc
ad: l-rl
ad: l-gcopper
ad: l-sarc
ad: l-innov
ad: l-WarrenG
ad: l-Waters
ad: l-tentec
DL7RU Germany flag Germany

Login is required for additional detail.

QSL: VIA BUREAU

Ham Member Lookups: 2453

QSL image for DL7RU

40m Mono-Band Mobil-Antenna for Roof Rack installation

Loading coil is 25.2µH / 21 Turns / Diameter 85mm / Lenght 84mm / Q : 953 at 7.18 MHz / Wire is 2mm CuL (enamelled Copper) / self (parallel) resonant at 31.7 MHz / Winding pitch 4 mm / Coil former 2mm GfK / Isolator tube through the coil is a 20x3mm GfK Tube and takes the bending moment

Matchbox:  LC-Low pass matching 7.9 Ohm to 50 Ohm / Choke Balun 11 Turns Coax-cable RG316 (50 Ohm Teflon) on FT140-43 Core. That decouples the outside braid of the Feed line from the Car body with -30dB / matching L (0.4µH) is Part of the Loading coil / matching C is 1020pF (470+330+220pF) to Ground / 100k 2 Watt Mox-Resistor to Ground for discharge static electricity

Two Antenna groundwires (6 mm2, red) are connected to the upper screws of the trunk door lifters

IC-7000 Controlling Unit clips on the grid of the freshair exhaust (with 3cm distance)

Antenna foot is made from a Boat stanchion base 25mm / a short piece of 23.5 x 1.5mm Aluminum tube is glued in with UHU-Endfest-300 Epoxy cement / Ground base is a part of a 20mm thick Acrylic board

Icom IC-7000 /  A Step-Up Converter (grey housing) gives me a regulated 13.8 Volt DC output for the Transceiver even if the Battery voltage drops down to 10.5 Volts / Battery is 12V/60Ah / They are no connections to the Car (wiring) except the Tuner grounding at the trunk door

Antenna roof rack is made by 19.5x19.5x1.5mm Aluminum square tube

All hose clamps are stainless steel / The U-Bolts are home made and bended from 6mm stainless steel threaded rods

Antenna Dates: Length above the Coil 123 cm / Lenght overall (from the bottom off the acrylicboard to the top) 155 cm / Radiating-Element is a Aluminum tube 23.5x1.5mm ( 100cm), upper adjustable Tuningelement (30cm) is 19.5x1.5mm / Input Impedance (jX=0) 7.9 Ohm at 7.061MHz / SWR with Matchbox at resonance point 1:1.02 / SWR 1:2 Bandwidth 27kHz / Upper end of the Antenna above Earth-Ground: 323 cm / 1mm in length variation gives 2 kHz in Frequency variation / calculated Antenna efficiency (with formula from DL9AH) ~ 78%

All Aluminum-Elements are from the DIY-Market see http://products.alfer.com/Produkte/Eisenwaren/combitech-System-Basis/System-Profile-Aluminium/Rundrohr.html

This Antenna considers the experience of Arno Weidemann (DL9AH) see www.dl9ah.de

Vy 73 Andy DL7RU   2014.07.31 

DARC-DOK: D01   -  e-mail: DL7RU@darc.de

2007  DK8NC

1224178 Last modified: 2014-08-30 05:43:28, 4284 bytes

Login Required

Login is required for additional detail.

You must be logged in to file a report on this page

Please login now...

Currently updating logbook display.
ad: giga-db
Copyright © 2014 by QRZ.COM
Sat Aug 30 12:14:29 2014 UTC
CPU: 0.053 sec 38985 bytes mp