Compaq FLEX-5000A manual Light Years Ahead, Transmitter Transmitter Dynamic Testing

Manufacturer’s Specifications	Measured in the ARRL Lab
FM adjacent channel rejection: Not specified.	20 kHz offset, preamp on:
	29 MHz, 59 dB; 52 MHz, 44 dB.
FM two-tone, third-order IMD dynamic range:	20 kHz offset, preamp on:
Not specified.	29 MHz, 59 dB*; 52 MHz, 44 dB*;
	10 MHz offset: 52 MHz, n/a.3
S-meter sensitivity: Not specified.	S9 signal at 14.2 MHz: preamp off,
	50 µV; preamp on, 50 µV.
Squelch sensitivity: Not specified.	At threshold, preamp on: SSB, 14 MHz,
	0.28 µV; FM, 29 MHz, 0.22 µV;
	52 MHz, 0.6 µV.
Audio output power: 10 dBV at 600 Ω.	As specified.4
IF/audio response: Not specified.	Range at –6 dB points, (bandwidth):
	CW (500 Hz): 345-856 Hz (511 Hz),**
	Equivalent Rectangular BW: 499 Hz;
	USB: 141-2851 Hz (2710 Hz);
	LSB: 140-2850 Hz (2710 Hz);
	AM: 71-3293 Hz (3222 Hz).
Image rejection: 70 dB.	First IF rejection, 43 dB5; image
	rejection, 88 dB.
Transmitter	Transmitter Dynamic Testing
Power output: HF and 50 MHz: SSB, CW,	HF: CW, SSB, FM, typically 100 W high,
FM, 100 W (high); AM, 25 W (carrier)	<1 W low; AM, typ. 25 W high, <1 W low;
	50 MHz: CW, SSB, FM, typ 99 W high,
	<1 W low; AM, typ. 25 W high, <1 W low.
Spurious and harmonic suppression:	HF, 51 dB; VHF, 61 dB.
HF, >55 dB; VHF, >65 dB	Meets FCC requirements.
SSB carrier suppression: >55 dB.	HF, 51 dB; VHF, 54 dB.
Undesired sideband suppression: >55 dB.	HF, 61 dB; VHF, 60 dB.
Third-order intermodulation distortion (IMD)	3rd/5th/7th/9th order (worst case band):
products: –33 dB PEP at 100 W on 14 MHz.	HF, –34/–40/–48/–54 dB PEP;
	VHF, –21/–32/–39/–40 dB PEP.
CW keyer speed range: Not specified.	1 to 60 WPM.
CW keying characteristics: Not specified.	See Figures 1 and 2.
Transmit-receive turn-around time (PTT release	29 ms.6
to 50% audio output): Not specified.
Receive-transmit turn-around time (tx delay):	25 ms.6
Not specified.
Composite transmitted noise: Not specified.	See Figure 3.

Size (height, width, depth): 9 × 9.3 × 12.4 inches; weight, 13 pounds.

Price: FLEX-5000A, $2799; antenna tuner option, $299; RX2 second receiver, $649.

*Measurement was noise-limited at the value indicated. **Varies with CW pitch setting.

1The level indicated is where the sound card’s ADC went into overload. Gain compression could not be measured because of this behavior.

2An input level of 0 dBm was higher than the ADC overload level, so the test was not performed. 3No IMD product could be detected.

4Audio output is dependent on external amplified speakers.

5Spur near the IF frequency. Note: The IF is in the audio range, so IF rejection will not affect RF performance.

6Measurements made with 1.6 GHz dual-core processor. Turnaround time may be faster with   higher speed CPU.

QS0807-PR01

0 0.02 0.04 0.06 0.08 0.1

Figure 1 — CW keying waveform for the FLEX-5000A showing the first two dits in full-break-in (QSK) mode using external keying. Equivalent keying speed is 60 WPM. The upper trace is the actual key closure; the lower trace is the RF envelope. (Note that the first key closure starts at the left edge of the figure.) Horizontal divisions are 10 ms. The transceiver was being operated at 100 W output on the 14 MHz band.

0				QS0807-PR02
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fc-4	fc-2	fc	fc+2	fc+4
		kHz

Figure 2 — Spectral display of the FLEX- 5000A transmitter during keying sideband testing. Equivalent keying speed is

60 WPM using external keying. Spectrum analyzer resolution bandwidth is 10 Hz, and the sweep time is 30 seconds. The transmitter was being operated at 100 W PEP output on the 14 MHz band, and this plot shows the transmitter output ±5 kHz from the carrier.

0	QS0807-PR03
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­really counts. The current maximum sampling rate (more on this topic later) permits viewing 192 kHz of band spectrum, with immediate access to both VFOs as well as to the panoply of major functions, most common, some less so. You access most functions via buttons, sliders, menus and sub-menus or tabs.

“Light Years Ahead”

What the FLEX-5000A brings to the table now is a far less complicated Amateur Radio

package that’s free of the surfeit of wires, cables, boxes and connectors that character- ized the SDR-1000. (Further eliminating the need for wires is VAC [virtual audio cable], third-party software that routes signals for digital programs to and from the FLEX- 5000A.) As one “Flexer” remarked on the FLEX-5000A Web site, “fit and finish are light years ahead of the SDR-1000” and “it looks like a professional radio.”

This ham radio system essentially consists

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Figure 3 — Spectral display of the FLEX-5000A transmitter output during composite-noise testing. Power output is 100 W on the 14 MHz band. The carrier, off the left edge of the plot, is not shown. This plot shows composite transmitted noise 100 Hz to 1 MHz from the carrier.

From July 2008 QST © ARRL