Potential radio harm?

Being it was just 5sec the radio was on and you didn't key the mic I'm 99.9% sure you did no damage.

Now if you had carried on a conversation(key the mic) for 1hr or something than that would be a different story.

 

Turning on your radio with no antenna attached, especially for that limited of a time will do no harm to your radio.

 

tru dat !!
keying the mic without an antenna (even for a few seconds) will make you cry though .

 

Well it won't actually go "Boom" but it will damage it. The is a certain amount of heat that gets transmitted through the coax and to the antenna and with out the antenna this heat gets pushed back in the radio itself and burns things up.

 

In fact it will be the final stage amplifier transistors. Without the antenna, the RF engery doesn't have an outlet and gets reflected back into the radio, quickly overheating the mentioned transistors.
But this only happens if you transmit. If you just receive without and antenna connected nothing will happen.

Jan

 

This is a very interesting thread. It happened to me 30 years ago and I burnt my finals. But. Some of the newer radios have safe guards ??? I know a guy that is a ham, he told me that he transmitted his 2 meter fm radio without the antenna. He forgot to hook it up. It did no damage to it. He said it had a safeguard. Kind of makes me think of the old idoit diodes they put in CBs in case you hooked the power up backwards.
I am also a ham. After 30 years on CB I wanted to try out CW ( morse code ) It's fun. But to each his own. I transmitted my Kenwood HF and wasn't hearing anybody. Turns out my Antenna was damaged. Checked the SWR and it was 4-1. Thought oh ###### I did it again. But when I fixed the antenna everything was still okay. I don't know why. Maybe CBs don't have this so called safeguard. I don't know. Maybe the higher end radios don't. Maybe I just got lucky.
TK

 

Most modern ham radios have a circuit, which controls the SWR and reduces output power if the SWR is more than 2.0 to prevent damage of the finals. Also many ham radios contain thermo switches, which prevent overheating the finals (even my 30 year old ICOM IC-701 HF transceiver has this feature). Obviously with 100W output power (which is industrial standard for HF ham radios these days) you can cook the finals quite fast if you don't pay attention.
Concerning CBs, at least the cheaper ones don't have it. Also, with the legal 4 Watts, cooking the transistors doesn't happen as fast.

Jan