REMARKS TECHNICAL SPECIFICATIONS
As with any other electronic circuit, the development of
Junior 1D was the greatest challenge to find the best possible
compromise. At a Product of this type should also have its
advantages and disadvantages be addressed.
Local Oscillator:
The local oscillator is obtained directly from the DDS. Unfortunately, DDS oscillators in this price class have their disadvantages. In addition to the main signal, many weak secondary
frequencies are included in the spectrum. This is shown by
disturbed reception areas. On: 5.1-8-8.5-9.4-10.4-11.7MHz,
this effect is strongest. When the antenna is connected, however, most “ghost signals” disappear under the noise. A plus
is the good phase noise of the LO, because the DDS output
signal is derived directly from 125MHz clock.
SSB reception:
In SSB reception, the upper and lower side bands is received
at the same time (DSB). The bandwidth is 6kHz. Only one SSB
filter with 2.7kHz bandwidth and with the appropriate overlay
frequencies would allow real single-page reception here.
SSB Smaller dynamics:
By directly feeding the SSB superimposed frequency from
455kHz into the A4100D, the AGC (Automatic Gain Control)
“pulls” by about 40db. Exactly this value goes in the
Scope of control. This can happen with strong SSB
Stations as distorted playback. Here, only a weakening of the
input signal brings relief.
A great plus of J1D is its simple operation, a very good
powerful sound in AM and its high assembly security packed
in a pleasing appearance
Useful tips before we start!
Put away the Speaker and not to unpack it.
Reason: The magnet can attracts small parts.
Empty all remaining plastic bags into a clean vessel.
There is no packaging system.
Have fun and success in building this Kit.
Heinz Stampfl
• reception area: 1,5-30MHz
• Modulation types: AM-DSB
• IF Filter: 10,7MHz ceramics
(Optional quartz filter 8Pol) 455kHz 6kHz BW 6Pol
• Dynamic Range AM: 95db
• Dynamic Range SSB: 55db
• SSB Method: Direct irradiation into the IF amplier
• Receiver principle: Doppelsuper 10,7MHz-455kHz
• Local oscillator: DDS(9850) 125MHz CLK
• Frequency steps: 10Hz, 100Hz, 1kHz, 5kHz, 9kHz
• Display: LCD 2x16 character
• Voltage range: 9-16V
• Power consumption: 300mA
• Battery Life: 8xAlkaline Typ AA ca.7h Akku 2100mAh ca.7h
• Height, width, depth: 150mm, 215mm, 150mm
• Weight: 0,85kg mit Batterien