Elmer Session Hand Out for 3/3/11 de W6WTI Some Common Controls Found On Amateur Radio Transceivers. (From ARRL web site tutorial) The placement of the controls may vary from manufacturer to manufacturer or on various models from the same manufacturer, however, the basic controls perform the same functions on all radios. 1. VFO - This is the main tuning knob used to tune in a station. This tunes your transmit and receive frequency and is shown on the MAIN DISPLAY. 2. METER- The meter in most radios is a multi function meter and shows a lot of information. Use this like the speedometer in your car; don't stare at it, but glance at it to make sure all things are proper. "S" or Signal strength - This indicates the relative strength of a received signal on a scale of 1 through 9. (W6WTI note: Signals above S-9 are measured in db above S-9, as in you re 10 over 9 here, old man. ) RF POWER - This shows how much power the transmitter is putting out. MAX is good SWR - This shows the Standing Wave Ratio of the antenna or how much power is being reflected back to the radio. MIN is good. ALC - This shows the condition of the Automatic Limiting Control circuitry. You want to make sure that you are not overdriving your transmitter. A good reading is when the (voice) peaks top the scale and stay within the range marked on the meter scale. 3. AF (gain) - This is the VOLUME control for the receiver. Audio Frequency gain. 4. RF GAIN - This control adjusts the gain of the receiver amplifier circuits. It allows you to make these circuits less sensitive so that you can dampen really strong signals. It is normal to see the S METER rise as you decrease the gain of the receiver by adjusting the RF GAIN.
5. MIC GAIN - This control the loudness of the microphone in any voice mode. It is best to adjust this for a good "in range" reading on the ALC meter. 6. MODE - This allows you to choose the mode of operation. CW - Continuous Wave (Morse code) USB - Upper Sideband LSB - Lower Sideband RTTY - Radio Teletype (Also FSK - Frequency Shift Keying) PKT - Packet (Also AFSK - Audio Frequency Shift Keying) FM - Frequency Modulation AM - Amplitude Modulation (added by W6WTI) 7. RIT - This stands for Receive Incremental Tuning and is used to fine tune a station you are listening to without changing your transmit frequency. It is sometimes called a Clarifier. 8. XIT- This is similar to RIT but it adjust your transmit frequency. It is Transmit Incremental Tuning. 9. RF PWR - Adjust the amount of transmitter power. 10. IF SHIFT- This shifts the center of the receiver's pass band. It allows you to avoid a signal that is close to yours by not letting it in the window of the receiver's pass band. 11. NOTCH - This is another good filter for reducing nearby interference. Unlike a window, it acts like a cover and blocks the signal that is in your window. 12. DSP - Digital Signal Processing Imagine looking through a Cracker Jack box and looking at street lights. You can only view the lights that are in your window. That's how the receiver's IF works. It can only receive signal if it's in the IF (Intermediate Frequency) window or PASSBAND. If you are looking at the lights and there is one to either side that you want to avoid then you can SHIFT the window. On the other hand, if there is a light in your viewing window that is distracting and if you shifted your window you would loose the light you want to look at, then you could slide your finger along the front of the viewing window until it just covered the unwanted light. That's how the NOTCH works. These two controls will help you pull out signals in a crowded band.
Some Other Controls You May Encounter (not in tutorial) As the ARRL Tutorial says, not every radio has every control. Over the last 50 years radios have become more feature laden with bells and whistles, some are more helpful than others. Here are an assortment of other things you may encounter. Bandswitch - Radios may have a bandswitch to select particular frequency segments. These may be physical switches with marked upper/lower limits, or buttons to toggle up / down. Some may have a MHz button so that increments of 1 MHz are selected, or jump between amateur bands. (Some radios receive HF ham bands only, some are general coverage. Several now incorporate 6 Meters and some even include 2 Meters, 440 MHz and 1200 MHz.) AGC or Automatic Gain Control - settings may be fast to slow. This setting helps keep strong signals from initially being too loud. Fast is helpful for CW, Slow is helpful for SSB. VOX/MAN/PTT - For voice operated transmit. Manual or Push To Talk relies on an external switch to transmit. Utilizing VOX is best with a desk or headset microphone. Adjustments for this function are VOX Gain (for sensitivity), VOX Delay (to set how long the radio stays in transmit before switching back to receive), and Anti-Vox (to minimize interference from the radio s speaker). This requires some adjustment for proper operation. For CW operation, using the VOX setting enables Semi-Break In. Some radios support Full Break In CW... when you hear received signals between individual dits and dahs as you send. Filter - The filters available in the radio may be switchable. In general wider filters are used for AM reception (3 to 12 KHz), narrower ones are used for SSB (1.8 to 2.7 KHz) and the narrowest ones are used for CW (1.8 KHz to 500 Hz). Some radios have two sets of filters, one for each of the radio s IFs. Processor - The Speech Processor provides audio compression to concentrate more RF power in your audio voice frequencies (sometimes called talk power.) Too much compression makes your voice sound harsh and may cause adjacent channel interference. Most processors have adjustments for how much to use. Follow the manual instructions for setting the processor. Keyer - some radios have a built in electronic keyer for CW operation. Typical control for this will be Key Speed. A special paddle must be plugged in to utilize this feature. Some may have memories built in to automatically send one or more pre-recorded messages, e.g. CQ CQ CQ de W6WTI W6WTI W6WTI AR K Memories - Memories are fundamental to VHF FM Repeater operation. Some repeaters are found on 10 Meters and 6 Meters. Memories are not so helpful on SSB HF because not all displays may be exactly the same and people tune for what is the best sounding voice. On SSB the bands are not channelized like repeaters on VHF/UHF; fitting in between QSOs on a quiet frequency is perfectly OK... but always check to see if the frequency is in use.
Memories can be helpful to enter WWV, WWVH e.g. 2.5, 5, 10, 15, 25 MHz, for time standards, or AM Radio stations e.g. 810 KHz, or foreign broadcast. (These stations sound best with wide filters like 6 KHz). Noise Blanker - your radio may have one or more. These help reduce interference from pulse type noise such as those from automotive ignition systems. Squelch - this control isn t particularly useful for SSB/CW/RTTY etc. It would be helpful in reducing background rushing noise when using FM repeaters. Fine Tuning - Changes the tuning ratio of the Main Tuning Knob... to facilitate precise tuning - particularly in congested CW signals, or rapid movement from CW to phone portions of the band. Tuner - Some radios have built in automatic tuning units to match the transmitter impedance with that of the antenna. Typical controls are thru/auto to bypass it, or put it in line. A tune control activates it and if the meter is showing SWR it should become quiet and show 1:1. Split, A/B or A=B - Even though most HF SSB operation is conducted on a simplex or same frequency, many DX stations - particularly DX-peditions and rare stations - operate split often by up to 10 KHz between their transmit frequency and where they are listening (often they ll say, listening up 10 to 20 KHz). Working these stations can be cumbersome or impossible trying to use RIT/XIT controls. A and B represent VFOs which can be set to different frequencies to facilitate listening to the desired station, and then listening to the station working that station as you set your transmit frequency. A=B puts both A and B VFOs on the same frequency as a prelude to moving your transmit frequency. Some current radios have increased the display to give you even more information about what s happening on each channel simultaneously. (Historical aside... in the old days transmitters and receivers were separate units and the challenge was to get them on the same frequency) Front Panel plug ins Microphone - the jack for your microphone or the mike part of a head-set. NOTE: not all jacks are the same. Check the manual to be sure you use the right impedance microphone. Phones - a convenient jack to plug in a set of headphones, or head-set. Back Panel connections Antenna, Ground, Power, Key, External Speaker
INITIAL SETTINGS In my Kenwood Manual there are suggestions for initial settings for SSB operation: 1. Ensure power is off 2. Antenna should be connected 3. Ground should be connected 4. DC power cable is connected to 12 VDC source (Power Supply or battery) 5. Plug in microphone 6. Put front panel controls and switches: a. Power Off b. Vox Off c. AGC Slow d. Notch Off e. AF Gain - fully counterclockwise f. RF Gain - fully clockwise To receive SSB 1. Turn power ON (turn power supply on first, if applicable) 2. Frequency should appear in display (if a digital display radio) 3. Tune to desired frequency... up/down or bandswitch and Main Tuning VFO 4. Select USB or LSB 5. Turn AF Gain clockwise until a signal or noise is heard 6. Rotate Tuning Knob to tune in a station or select open channel. To transmit SSB Radio is set as above 1. Press or select the Meter function as ALC 2. Press the microphone PTT or select Send on the panel. 3. Speak into the microphone and adjust the mike gain so that the meter deflection does not exceed the ALC zone on voice peaks. Conventions: LSB is used on 160, 75, and 40 Meters USB is used on 20, 15, and 10 Meters. Pay attention to your frequency and stay inside your authorized limits.