Radio Shack HTX-252 Owner's Manual

Cat. No. 19-1126OWNER’S MANUALHTX-242 TWO-METER MOBILE TRANS-CEIVERPlease read before using this transceiver.

10Using the HTX-242 as a Base StationAlthough we designed the HTX-242 primarily for use as a mobile transceiver, you can also use it as a base station

11Using the HTX-242 with Packet RadioYou can connect your HTX-242 directly to a packet radio terminal node controller, as shown below.Note: You can pu

12UNDERSTANDING THE HTX-242This section explains some of the HTX-242’s features. See “Basic Operation” on Page 16 for instructions about how to use th

13Subaudible Tone (CTCSS) FeaturesSubaudible tones, also known as CTCSS (Continuous Tone-Coded Squelch System) are low-frequency tones that are mixed

14Understanding the DisplayOne or more of the following indicators appear when you turn on and use your HTX-242.VFO-A or VFO-B — appears when you sele

15+ or – — indicates the duplex offset direction. See “Overriding the Duplex Offset” on Page 26.DTMF — appears when you turn on DTMF squelch. See “Usi

16BASIC OPERATIONTurning On/Off Your HTX-242To turn your HTX-242 on or off, press POWER. When you turn it on, all display elements briefly turn on and

17Setting Volume and SquelchSQUELCH sets the minimum signal level that must be present for the HTX-242 to amplify the signal through the speaker or to

18Selecting a FrequencyYou can select a frequency in any of three ways:• Direct entry• Tuning• ScanningDirectly Entering a Frequency1. Press VFO to se

19Scanning for a Frequency1. 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 Ste

2Your HTX-242 Two-Meter Mobile Transceiver is an exciting addi-tion to Radio Shack’s growing line of high-quality amateur radio equipment. It offers s

20Setting the Scan OptionsStoring Scan Skip FrequenciesYou can store up to five frequencies for your HTX-242 to skip when scanning. This lets you prev

21Setting the Scan Resume DelayWhen you set the scan resume condition to cr (carrier), the HTX-242 resumes scanning after the carrier drops. The scan

22Receiving TransmissionsTo receive a transmission, turn on the HTX-242, adjust the volume and squelch, and tune to the frequency you want to monitor.

23Manually Transmitting DTMF TonesTo transmit DTMF tones, follow the steps for transmitting. Then, while holding down PTT, press the digits on the mic

24Limiting Transmit DurationWhen you communicate on the 2-meter band, you should keep your transmissions as brief as possible. Most repeaters have bui

25ADVANCED OPERATIONFrequency Offset DefaultsWhen you select a frequency, the HTX-242 defaults to the following frequency offsets if auto duplex is tu

26Changing the Default OffsetFollow these steps to change the default offset for the VFO modes.1. Press VFO.2. Hold F for at least 1 second. FUNC flas

27Using the Dual VFOs for Duplex OperationFollow these steps to use one VFO to transmit and the other to receive.1. Press VFO to select VFO-A.2. Selec

28USING MEMORY CHANNELSThe HTX-242 has 40 standard memory channels and one calling-frequency memory, where you can store frequently-used frequen-cies,

297. 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 rec

3Programmable 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—rece

30Tuning to a Standard Memory Channel1. Press MR.2. Rotate M-CH, or press UP or DOWN on the microphone, to select the desired memory channel.Using the

31Scanning Memory ChannelsTo set the HTX-242 to scan memory channels, press and release MR. Then press and hold MR for at least 1 second. .flashes, an

32USING DTMF AND SUBAUDIBLE TONESYour HTX-242 has 10 DTMF (Dual-Tone, Multiple Frequency—another name for touch tones) memories where you can store DT

33Using DTMF PageDTMF page lets other operators page you. To turn on DTMF page, press DTMF so DTMF appears. The HTX-242 does not pass trans-missions t

34• Assuming all club members have DTMF page activated, to page everyone, transmit 465ABC.• To page West Side members, transmit 4654ABC.• To page Doug

35Using DTMF Auto SendIf you turn on the DTMF auto-send feature, the HTX-242 automat-ically sends the sequence stored in the currently-selected DTMF m

36Using Subaudible TonesSome repeaters require you to transmit a subaudible tone to acti-vate them. You can set your HTX-242 to transmit any of the 38

375. 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 tr

38USING THE MENUYour HTX-242 has a menu that lets you select how some functions work. The previous sections included procedures that access this menu—

39Menu ItemDefault OptionExplanation/Available Settings Page #SC tiScan resume option.ti—time out in 10 seconds.Cr—resume after carrier drops.SE—do no

4CONTENTSInstallation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Unpacking the Transceiver . . . . . . . . . . . . .

40TROUBLESHOOTINGError CodesYour HTX-242 has the following three built-in error codes.tF Err—appears if you try to transmit outside the allowed range

41Replacing the FuseYour 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

42SPECIFICATIONSGeneralFrequency Range (Factory)Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144 – 148 MHzReceive. . . . . . . .

43TransmitterRF Power Output . . . . . . . . . . . . . . . . . . . 45 W (high)/10 W (Low)Maximum Deviation . . . . . . . . . . . . . . . . . . . . . .

44SCHEMATICS

45RF SCHEMATIC

46DIGITAL SCHEMATIC

47MICROPHONE SCHEMATIC

Radio ShackA Division of Tandy CorporationFort Worth, Texas 761027A6 Printed in KoreaRadio Shack Limited WarrantyThis product is warranted against def

5Advanced Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Frequency Offset Defaults . . . . . . . . . . . . . . . . . . . . . .

6INSTALLATIONUnpacking the TransceiverAs you unpack the transceiver, check to be sure you have all the items shown in this illustration. Connecting th

7Mounting the HTX-242 in a VehicleWhen you select a mounting location for the HTX-242, be sure:• You can easily reach it• No wires or cables will inte

8Connecting an AntennaYou 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

9Connecting to your Vehicle’s PowerFollow these steps to power the HTX-242 in your vehicle.1. Connect the black wire to your vehicle battery’s negativ