Walkie talkies - Answers
Q1. Half-duplex communication is communication in both directions but not at the same time e.g. walkie talkies.
Q2. Simplex transmission is transmission that can happen in one direction only e.g. radio and TV broadcasts.
Q3. People often say 'Over' after speaking on a walkie-talkie.
Q4. There are 8 public frequencies.
Q5. There are 34 bands in each frequency.
Q6. The range of walkie-talkies can be up to five miles although many you buy are a lot less than that. The more you pay ....
Q7. Advantages and disadvantages of walkie-talkies compared to mobile phones: walkie-talkie handsets are cheap to buy and you don’t need to then rent a phone line or airtime or buy a SIM card or contract from any company. Handsets use rechargeable batteries so are cheap to run and they are small and highly portable. They don’t need to be licensed and a company can have as many handsets as they like using whatever public frequencies they like. Because the handsets use public frequencies, however, anyone can tune in to your conversations so they are not suitable for sending secure messages. Their limited range may be a problem for some applications. They can be large and you often need to have an aerial sticking out to receive signals. They have very few functions, apart from the ability to speak and listen - no apps or Internet connection.
Extension task
There are lots of useful questions students can ask when comparing walkie talkies to mobile phones. They may be able to come up with their own observations and comparisons. Students could also draw up and agree a list of objective criteria for comparing different walkie talkies.