JI1FGX/DU9 Mindanao, Philippines Amateur Radio Diary IOTA OC-130
English Japanese



Access up to yesterday
Introduction. 【【Lily Diary]
Diary of Life in Mindanao

09/12/16 Radio shop in Cebu, C5
09/12/15 diesel generator
09/12/13 Construction of Pipe Towers
09/12/06 2m repeater tour
09/12/05 Eve and Christmas Party
09/12/05 XYL and GiGi Class C Exams
09/11/30 RCS-10 Antenna Switcher Modification
09/11/21 DU9XO and eyeballs
09/11/20 eyeball QSO
09/11/20 General Meeting of PARA
09/11/19 To Manila for PARA's 77th Annual Meeting
09/11/18 Planning a DX Vacation
09/11/18 Planning a DX Vacation
09/11/17 controller of 2mFM repeater
09/11/15 Idling stop device made with AVR
09/11/14 Luggage, baluns, etc. from Japan
09/11/12 Postal Conditions in the Philippines
09/11/11 Lotlot-kun Antenna Building
09/11/09 144MHz Repeater Production Study
09/11/09 Request for Support
09/11/08 18MHz installation for EU completed
09/10/06 CWGet
09/10/28 Amplifier Eye
09/10/27 7MHz band extension modification
09/10/15 Car air conditioning repair
09/10/15 Balang arrives.
09/10/14 Split as the called party
09/10/14 Damage from Typhoon Manila
09/10/13 Arrival of filters from Japan
09/10/08 RTTY at 14 MHz
09/10/04 18MHz Antenna for Europe
09/09/26 CQWW RTTY Contest
09/09/25 birthday party
09/09/24 3.5MHz inverted V antenna
09/09/24 14M3EL Emergency Repair
09/09/22 Second 18MHz 3EL
09/09/21 Harvested rice
09/09/20 Communication with FT5GA
09/09/16 Handbook of PARA
09/09/15 FT5GA
09/09/13 Antenna for field operation
09/09/09 Pileups begin abruptly.
09/09/06 IOTA OC-235 Camiguin Island
09/09/03 CW Interface
09/08/30 antenna group
Aug. 27, 2009 Tower View
Aug. 26, 2009 18MHz 3-ele yagi installation completed
Aug. 24, 2009 Completed installation of 14MHz 3-ele yagi
Aug. 23, 2009 Correction of 18MHz Yagi
Aug. 20, 2009 144MHz 3-stage collinear
09/08/19 Adjustment of 14 MHz antenna
09/08/17 DV8UTP comes into play.
09/08/16 Coconut tower
09/08/13 14 MHz antenna
09/08/09 NHK WORLD shortwave broadcasting
09/08/07 Suzuki Light Truck
09/08/06 tower
09/08/05 hardware store
Jul. 31, 2009 FT-1000MP arrives.
09/07/25 Friends in Mindanao
Jul. 20, 2009 Antenna fabrication for 18MHz
09/07/19 Antenna for 144 MHz
09/07/14 Electronic Components Store
09/07/10 50 MHz antenna
09/07/09 Farm house and pigsty
09/07/02 CQ CQ CQ!
09/06/10 House construction and completion
09/05/29 Amateur Radio Antenna
09/05/28 Home construction and room conditions
09/05/01 Home construction and room conditions
09/04/17 rice harvesting
09/04/15 Rice harvesting soon
09/03/09 Home construction and room conditions
09/03/05 House building and electrical work
09/03/02 Go to Cagayan
09/02/28 Street corner scenery
09/01/19 Building a house and foundation
JI1FGX/DU9 Mindanao DiaryAmplifier I(2009/10/28)
XYL-Gigi has purchased the TV, DVD player, and speakers with built-in amplifier that he has always wanted!
He had been saving money for months.

The problem then was the speaker inside the amplifier.
I was going to buy a cheap one made in China for karaoke, so I let him choose a SHARP one that cost about twice as much.

This is because, by and large, the output of cell phones in this country can easily cause an amplifier to interfair!
Sure enough, the cell phone and 7MHz and 14MHz cause amp eye on the amp I have purchased!

So I called on Sharp's services and said, "I trusted Sharp and bought it, so please do something about it.I pressed him to say, "I'm sorry,
The only thing they suggested was, "Put AVR in it."
(Incidentally, even if a UPS is connected to the power line and powered by a battery, there will still be a wrap-around.

So Lotlot and I started looking inside.

Symptoms are that high-frequency waves easily come around from the connection cable even if the power of the wireless microphone receiver connected to the microphone terminal is turned off and on.
Generally, just plugging the cable of the wireless microphone receiver into the microphone jack of the loudspeaker will obviously increase the noise!

However, I also added a noise filter to persuade the Sharp engineers, who were skeptical about the power supply line.
However, since I just couldn't get a toroidal core, I disassembled my computer's power supply and put in a coil I took out!
But that didn't stop Amp I.
Note that no Amp I is generated on the LINE input terminal side from the DVD player (right side) other than the microphone terminal (left side).
The amplifier contained two operational amplifiers LM-324 and an IC called HT8970
I think I have a clue here.

I think I will be friends with this amp for a while to come!
Well, I can see why the microphone side has higher gain.
The output of the wireless microphone amplifier is deliberately lowered to the level of the microphone, and then amplified again by this OP amplifier.
October 27, 2009   November 06, 2009