What happened to the old TV signals?

The same spectrum is still largely used for TV, ie 6MHz channels starting at 56MHz now carry digital signals. Each 6MHz channel can carry about 29Mbps of data, enough for up to 10 standard definition digital sub channels or two high definition channels, usually one hi-def and maybe 3 standard def channels. These channels appear on digital TVs as their virtual channel number, ie channel 8.1 may actually be on UHF physical channel 42, as well as 8.2, 8.3 etc. In North America the OTA (over the air) standard is ATSC. In Europe they use DBV.

https://en.wikipedia.org/wiki/ATSC_standards

Some of the frequencies were allocated to the Digital hubs which is what you get your digital TV on, and others were sold off to mobile phone companies for 4G. However some of those frequencies do conflict with the digital signal in certain areas and so if you live close enough to a 4G mast you might need a 4G filter on your TV to receive Freeview (I presume btw we are talking UK here - other countries might have done other things with the frequencies).

If you look on Ofcoms website for 471Mhz-847Mhz http://static.ofcom.org.uk/static/spectrum/fat.htm...

The bandwidth that was being used for analog signals is now being used for the digital ones.

Brain damaged.

the tv signals are used now with digital modulation ... on the tv transmission system, you can change some boards to convert it to a digital one ....

on a digital tv channel (bandwidth 8 Mhz) you can transmit some channels at the same time but on an analog system, you can do ONLY ONE channel.

The have been sold to aliens from another dimension so they can watch all those old black and white series.

The spectrum is now turned over to emergency services like ambulance and police use. Some of the frequencies were turned over for some other uses, but I cannot remember what it was.

Parts of the spectrum they occupied are now used by the digital TV signals, but other parts of the spectrum were flogged off to the mobile phone operators - not as much as governments had intended because Digital has started to go HD and so more of the bandwidth than anticipated is still required for TV!

The frequency range was made available to mobile phone operators.