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E1800A FRONT

 

It must be remembered that the E1800A series are professional shortwave receivers with a great deal of flexibility. And for professional receivers this is quite rare, but possible due to its DSP design. Ultimately, this allows this model to stand out from the usual line and offer features that really make this radio the prefect DX receiver for broadcast, amateur band and monitoring in all modes. A nice feature is the ability to choose ANY filter bandwidth for ANY demod mode. This is almost unheard of in professional receivers where operator simplicity is paramount.

Front Panel (Right Hand Side) RHS

AF Level - Volume followed by two multifunction encoder controls. These control RF/IF gain, BFO, demod, filter bandwidth, passband tuning and notch filter.

The function of these two encoders is determined by the push buttons above each of these.

Notch filter

Operates in any demod mode and with all bandwidths.

Offers a very deep notch with 3 width settings, small (100Hz), medium (200Hz) and wide (400Hz). Tunable in 10Hz steps. Able to remove the strongest interfering carrier. But the following is really neat.... Once set the notch filter will track as you tune through the passband. In my view better than an auto notch as you can use this in CW and data modes without the risk of it masking the desired signal.

The lower row of red LED bars shows one segment to indicate the notch position. This combined with the tuning aid makes it very easy to get your notch dead on very quickly. The numeric display also shows the exact notch position relative to the centre of the receive passband.

IF Filter Bandwidths

There are more than an adequate number of IF bandwidths to choose from. Any filter is available in ALL reception modes. Each mode retains the last filter chosen. The filter width is represented by the red LED bars below the green tuning aid. Zero phase shift smooth roll-off response and steep response filters are provided, again for any mode you choose. Bandwidth is displayed as shown in the RHS picture.

Filters bandwidths (KHz) are:   0.1 - 0.2 - 0.3 - 0.4 - 0.5 - 0.6 - 0.8 - 1 - 1.2 - 1.3 - 1.5 - 1.6 - 1.8 - 1.9 - 2.1 - 2.2 - 2.4 - 2.5 - 2.7 - 2.9 - 3.1 - 3.4 - 4 - 5 - 6 - 8 - 10

Pass Band Tuning (IF Shift)

The IF passband can be shifted to remove or minimise interference. In fact, for example, in LSB the passband can be shifted to receive USB (if you really want to). Passband may be shifted upto +/-5KHz in 10Hz steps. The passband position is represented by the red LED bar below the green tuning aid. As the passband is moved, the tuning aid will only show signals within the IF passband window. Passband tuning is available in any demod mode and any bandwidth.

RHS picture BL+0Hz (bottom cutoff frequency). LHS pictures show AM signal on the tuning aid. Bandwidth set to 6KHz and IF filter shifted up by 1KHz. You can see this offset on the red LED bar.

Normally for SSB the default lower cuttoff is BL 300Hz.

Tuning Aid

this is a great facility for CW, AM and data modes. A very responsive display that is remarkably helpful. The scale/range of this bar changes automatically when the bandwidth and or passband tuning is used, to maximise the width of the LED bar. Works for all demod modes and bandwidths.

In operation the centre segment is red and the response of the display is instant as you tune in across a signal.

RF/AF Signal Level Meter

This bar is accurate across the complete range of RF input levels and is calibrate in dBuV EMF.

RF/AF button toggles between RF and AF measurement.

RF/IF Gain control

The usual slow and fast AGC modes are available. To set a threshold gain press the SQ button. The red LED bar below the green signal level LEDs will indicate the receivers maximum gain threshold, above which receiver gain will be limited. Adjustment is done using the control below Gain/Thr button.

In these two pictures the minimum signal level is set to +60dBuV.

Note that the Notch filter is also turned on and set to -2KHz below centre.

Tuning Rates

Three tuning rates are available; 1Hz, SLow and FAst

In SLow and FAst rates the receiver chooses the freq step size and steps per knob rotation, depending on the bandwidth and demod mode. For example as one would expect, in A1A(CW) narrow bandwidth, the tuning step is reduced to 20Hz in FAst and 10Hz in SLow. RHS picture in 1Hz tuning, showing both SL/FA LEDs off.

Setting & Using a Custom Frequency Tuning Step Size

Using the Scan Param button, setup a step size of your choice. Then press the Freq Scan button and choose a tuning speed using the SL FA button. That's it. Whenever the Freq Scan mode is on (but not running), you will be able to tune using your custom step size. So for example, set step to 9KHz and the steps per rev to suit and you can tune on each AM channel in the MW band.

The SL/FA key sets the number of steps per tuning knob rotation.

Demodulation Modes

A1A(CW) - A3E(AM) - J3E(SSB) - X3E - J7B - F3E(FM) - F7B(FSK) - F1B(FSK)

J3E, J7B, F7B and F1B are also settable to upper or lower sideband.

 

FSK Data Modes

Dedicated FSK modes are provided and may be decoded.

I have never tried these modes.

Channel Memories

100 channels are available to store frequency, filter bandwidth and demodulation mode. Each channel may be set with a flag to be ignored during scanning.

Notch, passband tuning and frequency step size are not stored.

Built in Test Equipment (BITE)

Test 00 is used to initiate a complete BITE test sequence.

Following successful completion of a BITE test sequence, the alpha display shows 'BITE finished'.

Individual tests may also be initiated to check specific areas of this receiver during diagnostic or alignment procedures.

 
 
More will be added to these pages as my time permits
If you have any questions or comments about this website, send me an email. I will read all but I can't guarantee that I'll reply to all. This is just a hobby site and my normal days work takes priority
I am not a trader or professional buyer or seller of these great bits of kit. It's just a hobby of mine to collect, play with, digest technical information and then either keep safe or pass on to another equally dedicated individual who will take care of these wonderfully engineered machines!
This website is not affiliated to any manufacture or model and the information contained is of my own work and as such, measurements and figures quoted are for reference only and are not intended to discriminate any individual product
2018 by Andrew Cygan