How to increase ring duration - HTC HD7 Cell Phone

You need to be able to reprogram your ECU (timing, duration), or need an aftermarket fuel computer (duration/volume). You will need to buy larger injectors in order to significantly increase the volume. This will also require a larger fuel pump and make the fuel computer a requirement.

go into the menu , phone set up scroll around until you get ring time/ duration and set for the desired no of rings before answer machine cuts in
down load a pdf version of the user manual for your system

The number of rings before your answring message picks up the call is controlled by your cellphone service provider. call in to your voice mail and then follow the instructions about going to options and setting. There should be a setting in there for the amount of rings to wait before answering the phone.

You can change the ringing type from "ring once" to "ringing". (Settings>>Profiles>>General>>Ringing Type)

or

you can choose a ringing tone with a longer duration.

Melnor 604F Instructions (from Label on unit)All indicator light flashing - replace 9V battery inside unit
1. To Start - turn dial to Off and press Enter.
2. Set Time - set current time and press Enter (Yellow ring).
3. Set Start Time - Set time to start first irrigation cycle (Yellow ring) and press Enter.
4. Frequency - Set frequency of irrigation cycle; e.g., twice a day set 12 h. (red sector ring) and press Enter
5. Duration - Set duration of cycle (Green band) minutes and press Enter.
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To change duration - turn dial to new duration and press enter.
To turn water on manually - Turn dial to ON position, water will turn off in 30 min.
Do not press enter in the OFF position as the unit will clear program. You will have to reprogram unit
via steps 2-5 above.

That requires disabling of a saftey device. NTHSA or others would not like instructions on that posted here.

Unlikely there is anyway to set a short duration timer.

you have to go into your settings and it will prompt long or short ring

how can i can L7 aduio volum can be increase  

No. Fax machines are designed to have their own dedicated fax lines.

Some newer models, tho, allow you to set NUMBER OF RINGS.

For a Telstra handset type into your phone.....
**61*101**30#