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Electronics => RF, Microwave, Ham Radio => Topic started by: Danesh_SA on August 11, 2017, 08:05:10 pm

Title: ASK Transmitter Problem
Post by: Danesh_SA on August 11, 2017, 08:05:10 pm
Hello ,
Recently I design a system and i use ASK 315 Mhz module with Pt2262 ,i use the circuit that i attached and i use 5V relay instead of 4 tact switchs and control them with MCU,the module voltage is 5v. the problem is: the module is always HOT! and when i send nothing the module draws 110ma @5v and when it transmite something it draws 110ma @5v too!
1-how can i turn off module when it not transmite anything?
2-Does the system warm up affect on module shorten range of transmition in long time(appr. 12 month and 8hours turn on every day)?
Title: Re: ASK Transmitter Problem
Post by: xtoffer on August 11, 2017, 09:06:14 pm
You could switch the power to the module on and off with some sort of transistor if it does not have a power down or enable pin. However 110 mA seems execessive. More information on which module, and the actual schematic would maybe help. If the module is the kind I think it is I would expect something in the order of ~10mA.
Title: Re: ASK Transmitter Problem
Post by: Danesh_SA on August 11, 2017, 09:48:16 pm
Thank for your reply xtoffer,
this module is much powerful and here is my schematic:

is it possible not to use PT2262 and directly connect the module to USART i found some projects on this subject , but is itreliable?