RadioShack HTX-242 - Manual

6 INSTALLATION Unpacking the Transceiver As you unpack the transceiver, check to be sure you have all the items shown in this illustration. Connecting the Microphone Plug the microphone’s connector into the microphone jack, secure the microphone holder to either the left or right side of the trans-c...

7 Mounting the HTX-242 in a Vehicle When you select a mounting location for the HTX-242, be sure: • You can easily reach it • No wires or cables will interfere with the vehicle’s operation • It is not directly in front of heating vents • All wires will reach their connection points Use the supplied ...

8 Connecting an Antenna You can connect a variety of antennas for both mobile and base-station use (see “Using the HTX-242 as a Base Station” on Page 10). Each type of antenna has its benefits. Choose one that best meets your needs. When deciding on a mobile or base-station antenna and its loca-tion...

9 Connecting to your Vehicle’s Power Follow these steps to power the HTX-242 in your vehicle. 1. Connect the black wire to your vehicle battery’s negative (–) terminal or to a metal part of the vehicle’s frame. Be sure the metal part is not insulated from the vehicle’s frame by a plastic part. 2. Co...

10 Using the HTX-242 as a Base Station Although we designed the HTX-242 primarily for use as a mobile transceiver, you can also use it as a base station. To do so, you need these items: • 13.8-Volt DC regulated power supply that can supply at least 10 amps continuous power • Base station antenna • 5...

11 Using the HTX-242 with Packet Radio You can connect your HTX-242 directly to a packet radio terminal node controller, as shown below. Note: You can purchase an 8-pin plug that matches your HTX- 242’s MIC jack at your local Radio Shack store (Cat. No. 279-440). Connecting an External Speaker (Opti...

12 UNDERSTANDING THE HTX-242 This section explains some of the HTX-242’s features. See “Basic Operation” on Page 16 for instructions about how to use these fea-tures. Dual VFO Modes The VFO (Variable-Frequency Oscillator) modes let you directly select a frequency anywhere within the HTX-242’s operat...

13 Subaudible Tone (CTCSS) Features Subaudible tones, also known as CTCSS (Continuous Tone-Coded Squelch System) are low-frequency tones that are mixed with a transmission. They are used by many repeaters to limit interfer-ence from other nearby radio transmitters. When a repeater uses a subaudible ...

14 Understanding the Display One or more of the following indicators appear when you turn on and use your HTX-242. VFO-A or VFO-B — appears when you select one of the VFO modes. See “Dual VFO Modes” on Page 12. VFO-A-TVFO-B — appears when you select the DUP-A mode (transmit on VFO-A and receive on V...

15 + or – — indicates the duplex offset direction. See “Overriding the Duplex Offset” on Page 26. DTMF — appears when you turn on DTMF squelch. See “Using DTMF Page” on Page 33. HIGH or LOW — indicates the transmit power level. See “Setting the Power Level” on Page 17. ON-AIR — appears when you tran...

16 BASIC OPERATION Turning On/Off Your HTX-242 To turn your HTX-242 on or off, press POWER . When you turn it on, all display elements briefly turn on and the HTX-242 sounds five tones. Then it returns to the last-used settings. Resetting the HTX-242 When you first use your HTX-242, if it displays P...

17 Setting Volume and Squelch SQUELCH sets the minimum signal level that must be present for the HTX-242 to amplify the signal through the speaker or to stop when scanning. Follow these steps to set the squelch. 1. Rotate SQUELCH fully counterclockwise. 2. Set VOLUME so you can hear the background h...

18 Selecting a Frequency You can select a frequency in any of three ways: • Direct entry • Tuning • Scanning Directly Entering a Frequency 1. Press VFO to select either VFO-A or VFO-B . 2. Enter the last five digits of the frequency. For example, to enter 145.050, simply press 45050 . Tuning to a Fr...

19 Scanning for a Frequency 1. Press VFO to select either VFO-A or VFO-B . 2. Press F . Then press ▲ to scan up or ▼ to scan down. Setting the Frequency Step The factory default frequency step is 20 kHz. Each time you rotate TUNE one click, or press UP or DOWN on the microphone, the fre- quency chan...

20 Setting the Scan Options Storing Scan Skip Frequencies You can store up to five frequencies for your HTX-242 to skip when scanning. This lets you prevent the HTX-242 from stopping on beacon or packet repeater frequencies. 1. Press VFO . 2. Hold F for at least 1 second. FUNC flashes. 3. Press MR ....

21 Setting the Scan Resume Delay When you set the scan resume condition to cr (carrier), the HTX- 242 resumes scanning after the carrier drops. The scan resume delay option lets you set the HTX-242 to pause before resuming so you can hear replies. The factory default is 2 seconds. Follow these steps...

22 Receiving Transmissions To receive a transmission, turn on the HTX-242, adjust the volume and squelch, and tune to the frequency you want to monitor. The HTX-242 displays BUSY , and the signal-strength indicator shows the relative signal strength when it receives a signal. Note: If BUSY appears b...

24 Limiting Transmit Duration When you communicate on the 2-meter band, you should keep your transmissions as brief as possible. Most repeaters have built-in timers that limit single transmissions to 3 minutes or less. You can set the transceiver to stop transmitting and sound a beep if a single tra...

25 ADVANCED OPERATION Frequency Offset Defaults When you select a frequency, the HTX-242 defaults to the following frequency offsets if auto duplex is turned on: The default offset is 600 kHz. For example, if you tune to receive 146.940 MHz, the HTX-242 automatically transmits at 146.340 MHz (600 kH...

26 Changing the Default Offset Follow these steps to change the default offset for the VFO modes. 1. Press VFO . 2. Hold F for at least 1 second. FUNC flashes. 3. Press SHIFT . The HTX-242 displays oS and the current offset (in MHz). 4. Rotate TUNE , press UP or DOWN on the microphone, or directly e...

27 Using the Dual VFOs for Duplex Operation Follow these steps to use one VFO to transmit and the other to receive. 1. Press VFO to select VFO-A . 2. Select a frequency. 3. Press VFO to select VFO-B . 4. Select a frequency. 5. Press DUP . When the HTX-242 displays: VFO-A-TVFO-B it transmits on the V...

28 USING MEMOR Y CHANNELS The HTX-242 has 40 standard memory channels and one calling-frequency memory, where you can store frequently-used frequen-cies, along with all settings, for quick access. Storing a Frequency 1. Press VFO and tune to a frequency you want to store. Set all duplex and subaudib...

29 7. Press ▲ . The HTX-242 displays rC and the current receive subaudible tone. 8. Rotate TUNE , or press UP or DOWN on the microphone, to change the receive subaudible tone. 9. Press ▲ . The HTX-242 displays tC and the current transmit subaudible tone. 10. Rotate TUNE , or press UP or DOWN on the ...

31 Scanning Memor y Channels To set the HTX-242 to scan memory channels, press and release MR . Then press and hold MR for at least 1 second. . flashes, and the HTX-242 scans memories that have the scan option turned on (see “Enabling/Disabling Scanning for Memory Channels” on this page). The HTX-24...

32 USING DTMF AND SUBAUDIBLE TONES Your HTX-242 has 10 DTMF (Dual-Tone, Multiple Frequency — another name for touch tones ) memories where you can store DTMF sequences. DTMF Memory 0 can hold a 7-digit DTMF paging sequence your HTX-242 must receive for DTMF paging. DTMF Memories 1-10 each hold 15 di...

33 Using DTMF Page DTMF page lets other operators page you. To turn on DTMF page, press DTMF so DTMF appears. The HTX-242 does not pass trans- missions to the speaker until it receives the sequence you stored in DTMF Memory 0. If DTMF Memory 0 is empty, DTMF page does not operate. When you receive a...

34 • Assuming all club members have DTMF page activated, to page everyone, transmit 465ABC. • To page West Side members, transmit 4654ABC. • To page Doug and Cary, transmit 46518ABC. • To page only one person, transmit the 7-digit sequence. Using Auto-Reply If you turn on the auto-reply feature, the...

35 Using DTMF Auto Send If you turn on the DTMF auto-send feature, the HTX-242 automat-ically sends the sequence stored in the currently-selected DTMF memory every time you press P TT. Follow these steps to turn on auto send. 1. Press VFO . 2. Hold F for at least 1 second. FUNC flashes. 3. Press MR ...

36 Using Subaudible Tones Some repeaters require you to transmit a subaudible tone to acti-vate them. You can set your HTX-242 to transmit any of the 38 standard subaudible tones. You can also limit incoming reception by setting the HTX-242 to open the squelch only when someone transmits a subaudibl...

37 5. Press ▲ . The HTX-242 displays tC and the currently set transmit tone. 6. Rotate TUNE , or press UP or DOWN on the microphone, to set a different transmit tone. If you do not want a transmit tone, select oFF . 7. Press T-SQL or P TT to save the settings. Activating Subaudible Tone Transmit and...

38 USING THE MENU Your HTX-242 has a menu that lets you select how some functions work. The previous sections included procedures that access this menu — this section provides an overview. Follow these steps to use the menu: 1. Press VFO . 2. Hold F for at least 1 second. FUNC flashes. 3. Press MR ....

40 TROUBLESHOOTING Error Codes Your HTX-242 has the following three built-in error codes. tF Err — appears if you try to transmit outside the allowed range (see “Extending the Transmit Frequency Range” on Page 16). PLL Err — appears if the HTX-242’s PLL (phase-locked loop) sec- tion malfunctions. If...

41 Replacing the Fuse Your HTX-242 (and vehicle) are protected by a 15-amp fuse in the HTX-242’s positive (red) power wire. If the HTX-242 does not turn on, even when you are sure the power wire is properly connected to a 12V DC power source, check the fuse and replace it, if necessary. 1. Snap open...

42 SPECIFICATIONS General Frequency Range (Factory) Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 – 148 MHz Receive. . . . . . . . . . . . . . . . . . . . . . . . 136.000 – 174.000 MHz Frequency Step . . . . . . . . . . . . . . 5/10/12.5/20/25/50/100 kHz Frequency Stability ...

43 Transmitter RF Power Output . . . . . . . . . . . . . . . . . . . 45 W (high)/10 W (Low) Maximum Deviation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 kHz Hum and Noise . . . . . . . . . . . . . . . . . . . . . . . . Better than 35 dBAudio Distortion . . . . . . . . . . . . . ...