Radio repair DIY
Models: M1 Mega Paper
Symptom: M1 words can not send outgoing intercom
Fault diagnosis: Air over the Prophet!!
I am not a professional maintenance staff, wrote this record, is I want to share the fun of repair and exchange service experience, record writing is not good, please do not laugh.
No professional workstations, on the home front to open a small table, and then put on the usual tools, that is, some Rose knife, multimeter and tweezers and hot air units. The first demolition intercom, hard not to feel a little nervous and excited, not afraid of bad repair, mainly because the M1 ruined!!
No circuit, the line did not know it works, but open look, my heart always a little disappointed, M1 board indeed "too simple" domestic thing is the cow! But you pay for ah! First on Figure: [img] [/ img]
Test, it was found, M1 incoming normal, but in using the M1 exhaled when another radio PX777 not receive M1 sound, frequency is the same, tone is the same, so it is estimated that the machine hardware fails, Later hired the M1 headphones and found the two sides are normal incoming and outgoing calls, thereby estimated M1 hardware failure should not be a big problem, because technology, however, can even say that there is no technology at all in this area, so I will sights on two places, focusing on the investigation of these two places: the first one is the headphone jack; second is M1 fuselage MIC.
Remove the headphone jack, direct observation of eye sockets, which the contact pads no obvious distortion or deformation, with the meter to measure, nor anything unusual, so the focus will put on the MIC (If other signal amplification circuit, I believe I have no way to engage the people, ^ _ ^ ^ _ ^)
Fearing damage to the chip static electric iron, so then still put on a hot air units, the MIC welding, using a multimeter to measure, is through, but with the mouth on the MIC blew several times and found the multimeter reading does not change, think this pickup microphone with a D suspicious, they got a wife phone (of course, is bad, I do not want my life!!), remove the phone's MIC, welded directly to the radio up, power test, just press the PTT, also did not say something that will be issued next PX777 strident voice, immediately get away to try again, no problem, once installed, Oh, so excited!!
On the repair process is summarized and analyzed, 1, M1 plug in headphones, but also to send, it indicates that the two radio QSO aspects of the signal is no problem, focusing on aspects of speech signals observed M1 on it. 2, pick words is a relatively easy damage of electronic components, to be more careful in the measurement, the test can be used with a table for pickup microphone mouth blown it, then pick up the normal, typically with the corresponding pointer will swing it.
These are my walkie-talkie in the maintenance of some of the ideas in the process, we hope to solve some minor glitches in the DIY helpful when