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All manuals and user guides at all-guides.com Cat. No. 19-1126 OWNER’S MANUAL HTX-242 TWO-METER MOBILE TRANS- CEIVER Please read before using this transceiver.
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License and a call sign issued by the FCC to legally transmit using this transceiver. Transmitting without a license carries heavy penalties. Get- ting a license is easier than ever. Your local Radio Shack store has train- ing materials for all classes of Amateur Radio Operator.
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All manuals and user guides at all-guides.com Programmable Frequency Step—lets you set the frequency step for tuning or scanning to 5, 10, 12.5, 20, 25, 50, or 100 kHz. Extended Band Coverage —receives from 136 to 174 MHz and lets you extend transmit coverage to include 2-Meter ham, MARS (Military Amateur Radio Service), and CAP (Civil Air Patrol).
All manuals and user guides at all-guides.com 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- ceiver, then clip the microphone to the holder.
All manuals and user guides at all-guides.com 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 •...
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.
10-amp maximum power draw. Or, if you do not want the HTX-242 to turn on and off with your vehicle’s ignition, connect the red wire directly to the battery’s positive (+) terminal.
All manuals and user guides at all-guides.com 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: •...
All manuals and user guides at all-guides.com 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...
VFOs to tune to frequencies you have not stored into one of the HTX-242’s memory channels (see “Memory Channels” on Page 13). A related feature of the HTX-242 lets you transmit on the fre- quency selected with one VFO and receive on the frequency selected with the other VFO.
Your HTX-242 includes all 38 standard subaudible tones. You can set your HTX-242 to include any of these tones with your trans- missions. You can also set your HTX-242 to limit reception to only those transmissions that include the selected tone.
VFO-A and transmit on VFO-B). See “Using the Dual VFOs for Duplex Operation” on Page 27. BUSY — appears when the HTX-242 is receiving a transmission. See “Receiving Transmissions” on Page 22. — appears after you press . Flashes after you hold...
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All manuals and user guides at all-guides.com – — indicates the duplex offset direction. See “Overriding the Duplex Offset” on Page 26. — appears when you turn on DTMF squelch. See “Using DTMF DTMF Page” on Page 33. HIGH — indicates the transmit power level. See “Setting the Power Level”...
Resetting the HTX-242 When you first use your HTX-242, if it displays PLL Err , or if you ever want to reset the HTX-242 to the factory defaults and clear all memory, follow these steps. Important: This procedure clears all stored information.
Setting Volume and Squelch sets the minimum signal level that must be present for SQUELCH the HTX-242 to amplify the signal through the speaker or to stop when scanning. Follow these steps to set the squelch. 1. Rotate fully counterclockwise.
DOWN through the frequencies. Notes: • You can set the HTX-242 to step in 5, 10, 12.5, 20, 25, 50, or 100 kHz increments. The default is 20 kHz. See “Setting the Frequency Step” on Page 19. • To step in 1 MHz increments, press .
Notes: • You can set the HTX-242 to scan in 5, 10, 12.5, 20, 25, 50, or 100 kHz steps. The default is 20 kHz. See “Setting the Frequency Step” on Page 19. •...
All manuals and user guides at all-guides.com 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.
(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 to change the scan resume delay.
HTX-242 transmits at high power (about 45 watts). To return to low power, press again. • If you try to transmit outside the permitted range, the HTX-242 dis- plays tF Err and beeps twice.
Note: If auto-reply is turned on, you must hold down PTT while you trans- mit. If auto-reply is off, you can release PTT after you enter the first digit. The HTX-242 transmits for 1 second after you enter the last digit. See “Using Auto-Reply” on Page 34.
PTT to save the settings. Turning the Keytone Beep On and Off Your HTX-242 sounds a beep each time you press a button. Follow these steps to turn off this keytone beep. Note: This does not affect the tone-alert beep, alarm scan beep, or the transmit limit beep.
All manuals and user guides at all-guides.com 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: Receive Frequency Transmit Offset Below 144.600 MHz No offset (Simplex) 144.600 to 144.905 MHz...
Overriding the Duplex Offset When you tune to a frequency, the HTX-242 automatically selects either simplex operation, or duplex operation with the correct off- set direction (if the auto duplex option is on). To override this set- ting, press .
VFO-A 2. Select a frequency. 3. Press to select VFO-B 4. Select a frequency. 5. Press When the HTX-242 displays: VFO-A-T VFO-B it transmits on the VFO-A frequency and receives on the VFO-B frequency. When it displays: VFO-A VFO-B-T it transmits on the VFO-B frequency and receives on the VFO-A frequency.
All manuals and user guides at all-guides.com USING MEMORY 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 and tune to a frequency you want to store.
). Then press save all settings. Using Auto Memory Store (AMS) Follow these steps to have the HTX-242 scan through a selected range and store active frequencies in memory. 1. Set the upper and lower scan limits (see “Setting the Scan- ning Range”...
The HTX-242 looks back at Memory Channel 1 every 4, 8, 12, or 16 seconds. If there is a transmission, the HTX-242 beeps to let you know to tune to it, if desired. Follow these steps to change the look-back time.
All manuals and user guides at all-guides.com Scanning Memory Channels To set the HTX-242 to scan memory channels, press and release . Then press and hold 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”...
3. Press the push-to-talk button. While holding down PTT, press . The HTX-242 transmits the stored sequence. DTMF Note: If the DTMF auto send feature is turned on, the HTX-242 transmits the tones in the selected DTMF memory every time you press PTT.
DTMF Memory 0. If DTMF Memory 0 is empty, DTMF page does not operate. When you receive a DTMF page, the HTX-242 turns on the speaker and turns off DTMF page so all transmissions come through. Notes: •...
• To page only one person, transmit the 7-digit sequence. Using Auto-Reply If you turn on the auto-reply feature, the HTX-242 automatically sends the sequence stored in the currently-selected DTMF memory when it receives a DTMF page. Follow these steps to turn on auto-reply.
After the transmission, DTMF squelch is still turned on. • If there is no sequence stored in DTMF Memory 0, the HTX-242 still transmits the currently selected DTMF memory sequence each time you press PTT, but passes all transmissions to the...
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 subaudible tone you select.
Setting the DTMF Page and Subaudible Tone Alert When the alert function is turned on, the HTX-242 sounds a sequence of three tones when it receives a DTMF page (if DTMF page is activated) or a transmission that includes the correct sub- audible tone (if tone squelch is activated).
All manuals and user guides at all-guides.com 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.
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—do not resume scanning. Scan delay (delay before resume when is set to , or Scan skip frequency 1 (frequency for –––.––– HTX-242 to skip when scanning VFO). Scan skip frequency 2. –––.––– Scan skip frequency 3. –––.––– Scan skip frequency 4.
—appears if the HTX-242’s EEPROM checksum fails. Try resetting the HTX-242 (see “Resetting the HTX-242” on Page 16). If this does not clear the error, take it to your local Radio Shack store to arrange for service. Common Problems and Solutions If your HTX-242 does not seem to be operating properly, check this section for a possible solution.
HTX-242. If the fuse frequently blows, there is a problem with the HTX-242 or its wiring. Have that problem fixed as soon as possi- ble. 4. Replace the fuse in the holder and snap it closed.
All manuals and user guides at all-guides.com SPECIFICATIONS General Frequency Range (Factory) Transmit ......144 – 148 MHz Receive.
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All manuals and user guides at all-guides.com Transmitter RF Power Output ....45 W (high)/10 W (Low) Maximum Deviation ....... 5 kHz Hum and Noise .
All manuals and user guides at all-guides.com SCHEMATICS...
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All manuals and user guides at all-guides.com RF SCHEMATIC...
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All manuals and user guides at all-guides.com DIGITAL SCHEMATIC...
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All manuals and user guides at all-guides.com MICROPHONE SCHEMATIC...
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Within this period, we will repair it without charge for parts and labor. Simply bring your Radio Shack sales slip as proof of purchase date to any Radio Shack store. Warranty does not cover transportation costs. Nor does it cover a product subjected to misuse or accidental damage.