Motorola visar MODEL H05RDH9AA7AN - Motorola Visar Dual Charger Aa16742 For 7.5v Battery

This is a discontinued radio from Motorola. programming requires a cable to connect to a computer, there is no direct programming available.
While this is not really an answer, the programming software is specific to Motorola and you need to buy both the software and the cables from Motorola.
you would be better served, to determine what frequencies you want and then pay a certified Motorola dealer who has the software to do the work for you.

You probably need to have the radio re-programmed. There is no other way to reset it.

These radios were available in many frequency ranges from VHF through 800MHz. You can decode your radio's model number to tell what band your radio should be in.

You can use this chart to decode your model number. See http://www.batlabs.com/visar.html for more information about these radios.

The radio is easy to disassemble and has no hidden surprises, but I doubt you're going to like what you see once you get it apart. The large screws that are very visible on the outside hold both halves of the outside to the thick radio chasey and mother board.

Your volume problem is typical for older T6400s, and is caused by the speaker binding internally. Motorola does not sell the speaker separately and it is built into the case so you can't really just un-hook it and install a new one in it's place.

That's a shame, they are great radios.

Do you mean Motorola Visar?
If that what you are asking no it is not.

Your radio needs to be programmed for one channel to duplex. Duplexing is when a channel has a different frequency for transmit than for receive. (Not all radios are capable of doing this.)

A repeater listens on one frequency and then retransmits what it hears on another frequency. See your local radio dealer for more info, and to see if your radio is repeater capable.

The Visar has a channel lock feature. If you hold down the two channel buttons at the same time, it will do one of two things depending on the settings. Either the channel will lock, or the channel numbers in the LCD will flip.
If you press the channel button and the "popples" "pop" (for lack of a better word) then the channel selection buttons re most likely OK. To fix it you just press both channel buttons at the same time for about 5 seconds. It will beep and you should be able to change the channels. If not, then it needs to be repaired.

The HT1000 is a dealer programmable unit. The DTMF keypad on the front of the unit would be nonfunctional unless you were using it in conjunction with a repeater system which allows for DTMF phone capabilities. Otherwise it is just an extra place for dust, dirt and moisture to get in the radio. If you are working as a firefighter, it is highly recommended you get a holster to cover the front of the radio to prevent moisture from getting to the component board through the keypad area. As for telling if the radio is VHF or UHF, typically the 4th digit of the model number will tell you. If it is an R it is UHF; if it is a K it is VHF. Here is a link to a reference chart: http://www.batlabs.com/visar.html#5

If you need to re-program the GP340's here is a link to some software on Ebay. You would need to buy a cable to connect the radio to the pc, but these cables can be found on Ebay also.

The radios have to be programmed by a RSS (Radio Service Software) and a RIB (Radio Interface Box) is needed. You can learn more about hat by going to www.batlabs.com additionally, the VISAR page is http://www.batlabs.com/visar.html

If you want to buy a RIB you can get the software and programming info at http://www.ham.dmz.ro/motorola/visar.php