AOR AR7030m Operation Information Manual

AR7030 OPERATING MANUAL          PAGE 31
11 Aerials (Antennas) and earth systems
The subject of aerial choice (and earth) can be quite
complex. There are many advantages and disadvantages
of each aerial type to consider before connecting an
external aerial to your receiver.
One interesting phenomenon is that aerial theory and
practice can be surprisingly different. Within common
sense bounds, aerial construction is one of the few
remaining areas for listeners to easily experiment and often
achieve...

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system. If in doubt consult an experienced electrician.
Connecting an external earth wire may greatly reduce the
local noise encountered when listening on the short wave
bands. It is very important to provide a good earth should
you use an aerial tuning unit.
A short length of thick gauge earth wire may be connected
to a nearby central heating radiator or water pipe but never
use a gas pipe for earthing. Ideally a separate earth rod
should be used but not if the...

AR7030 OPERATING MANUAL          PAGE 33
13 Technical specification
Performance figures relate to a typical production receiver and are not guaranteed levels.
Test signals:- AM mode : Modulated to 70% depth at 1kHz
FM mode : Deviated by 1.5kHz at 1kHz
SSB  mode  : Unmodulated carrier, resolved at 1kHz
1. Receiver system
Dual conversion super heterodyne system with intermediate frequencies of 45MHz and 455kHz.
High dynamic range mixer using a DMOS lateral FET quad.
Tuning by single loop PLL / DDS system...

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 5. R F Input
Three antenna inputs (selected by rear-panel switch) :
50ohm unbalanced via SO-239 connector.
600ohm unbalanced via wire grip connector.
Hi-Z whip input (on SO-239) with reduced R F performance.
R F band split at 1.7MHz with high-pass and low-pass filters.
R F pre-amplifier and attenuators give +10 / 0 / -10 / -20 / -30 / -40dB R F Gain.
  Switching is automatic with manual override.
6. I F System
Four I F filters fitted as standard, nominal...

AR7030 OPERATING MANUAL          PAGE 35
11. Selectivity
The following data is taken from measured performance of the 455kHz I F system and ignores effects of the
45MHz roofing filter and any audio frequency response tailoring. AGC was switched off.
Filter stop-band attenuation : All filters > 110dB
2.2kHz filter characteristics : -6dB bandwidth : 2.29kHz
-60dB bandwidth : 3.34kHz
-80dB bandwidth : 4.98kHz
6/60 shape factor : 1 : 1.46
5.5kHz filter characteristics : -6dB bandwidth : 5.54kHz
-60dB...

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Second order intermodulation effects : Measured as above with two signals of 0dBm at around 12.7MHz,
resolving the SUM frequency at 25.5MHz.
Intermodulation-free dynamic range : 104dB 2nd order intercept point : +85dBm
13. Spurious responses
Unwanted signal rejection : Quoted figures are the levels of unwanted signal, relative to wanted, required to
produce a similar S+N/N ratio. Many figures vary depending on the frequency the
receiver is tuned to, so ranges of...