The National Panasonic DR-29/ RF-2900 is a portable shortwave receiver with
a very similar construction like the DR-28 / RF-2800, it's
dimensions of 38 x 25 x 12 cm and it's weight of 3,6 kg are identical to the DR-28,
the only difference is the switchable preselector located in the upper part
of the front panel.
The receiver can be powered from 110 / 220 V mains or 6 UM-1 / mono cells.
At the left part of the front panel, the space is taken by the speaker grille,
audio quality is good thanks to an output power of 2.3 Watts.
The switchable preselector is located just above the speaker grille. When the
preselector is activated, You have to operate a second wave range switch and the
preselector control to peak the incoming signal. The preselector will improve signal
strength of the selected frequency and reject signals from frequencies outside
the tuned center frequency, so finally a lower total signal level will arrive
at the R.F. amplifier / first mixer and the set is less likely to overload. But be careful: with
the preselector set to a wrong frequency, the incoming signal is attenuated and You
won't hear anything from the speaker, so it might make sense to first tune in a station
with the preselector switched off, then activate it and peak to maximum S meter reading.
At the top of the right half of the front panel, You find the rotating analog frequency
dial with coarse markings that give You an impression, to which part of the shortwave
spectrum You are tuned to. Next to it, You find the green - blue fluorescent
frequency display with a resolution of 1 kHz.
In a row of controls just below, You find from the left the mains switch, the
dial illumination and tha wide and narrow I.F. filter switch. The signal strength
meter tends a bit to overestimate signal strength, next to it, You find the bandswitch
and the switch to turn of the energy consuming frequency display, this might also
be helpful in case of "birdies" caused by oscillations from the frequency
In the middle, You find the huge main tuning knob, it can be pulled out to activate
a geared fine tuning mechanism. It it's left, You find the big volume control and
slighly smaller separate bass and treble controls and the connectors for an
external speaker and a cassette recorder.
The control at the right SW CAL ist used to calibrate the frequency display,
in fact it corrects the frequency display's reading to the frequency that is
actually received. As the control range is quite big, it can happen, that the frequency
displayed is up to 5 kHz off the reading of the frequency counter. So make sure,
You first tune in to a stations with a known frequency in a shortwave band,
carefully tune for maximum reading on the signal strength meter and then
adjust the reading of the frequency display to the known station's frequency.
The R.F. control is used to vary the high frequency amplification, in fact
a kind of automatic gain control is always active, so the RF gain control
is merely used like a step - less attenuator in the case of the presence of strong
signals. As the DR-29 tends to overload with high signal strength, this might be
the case from time to time in central European winter nights on 49 meters. The
BFO has a separate switch and beat note control.
The R.F. signal coming from the antenna first has to pass the preselector
stage, only the signals in the tuned frequency range will be forwarded without
attenuation to the R.F. amplifier stage and the RF gain control and then
be fed to the first mixer. After an I.F. amplification
the signal is mixed to the widely used 455 kHz as second intermediate frequency.
In AM mode, a diode demodulation is used, for CW and SSB reception, the BFO's
signal is added before demodulation. The oscillator frequency from the first
mixer is used to drive the frequency counter.
The DR-29 does a good job as a simple world band receiver that can meet
some DXer's expectations. Thanks to the preselector, the capabilities to handle
high signal level situations without spurs and "ghost signals"
appearing on strange positions on the dial are better then with the DR-28.
Especially with a long wire antenna
connected, the receiver tends to overload: You have to reduce the R.F. gain
to end with a S meter reading between 8 and 10.
The sensitivity is quite good, selectivity is fair with the narrow filter,
the WIDE filter can only be used on channels without interference from
The DR-29 shows a slight drift, it may be detuned up to 4 or 5 kHz after
one hour of use, automated recordings of single sideband transmissions or even
decrypting radioteletype signals with a converter might be found difficult
or even impossible.
The fact, that the real and the frequency displayed from the counter might
have a difference of up to 4 or 5 kHz reduces the benefit from the frequency counter.
The performance on the VHF / FM broadcast band ist good, especially in comparicon
with other sets doming from Japan.
In conclusion: the DR-29 / RF-2900 is a really useful shortwave radio for
listeners interested in getting some informations directly from abroad from
the External services of the major international shortwave broadcasters and
even for DXers for their first steps in the Hobby. For everyday and travel use,
a PLL synthesized receiver with some memories and without the drawbacks of the
frequency counter shift and poor performance under high signal level conditions,
might be the better option.
On the used market, the DR-29 with the preselector would be a nice catch, if the price
is acceptable, the DR-28 without the preselector is expected to be sold for a lower