China-made toy-drones

There are many drone factories in Shenzhen, China. And there are many models available in Hong Kong. The following is my first drone or quad-copter.  Day one I lost the control of my first drone and hit it strongly against the ceiling of my room and the shaft of the two tiny motors (coreless motors) were broken. No use any more so I opened it to check the inside. Actually it has no cover so just broke it apart. The major three ICs were found on this mini quad-copter. This is a high-tech toy.

ST Micro MPU 32F030F4P6
Gyro IC M688(099LB1L122)
2.4G Wireless Tranceiver IC XN297L

This will continue.

China made SW radios review - 2, Kaide KK-2005 New model

I introduced Kaido KK-2005A in the previous post "China made SW radios review". As I recently found this model with the new technology  - poptentiometer tuning I would like to compare the new model with the old  model.


Kaide KK-2005A  - Old and New

The old and mew models are exactly the same in outlook and even the model name KK-2005A. The basic functions are also the same FM/AM/SW(7 bands). The retail prices are also the same about US$15.

What are the differences ?

Slight but noticeable difference are weight and sound. Big differences are inside.

1) Insides

We can find revolutionary changes between the old and new inside. Please see below.


a) Old model


One side

You can find that the PCB name is KK-2005 and one PVC (Poly Vari Con), four IFTs, 3-4 Ceramic Filters, several Air Coils and many Ceramic Disc Caps for tuning.  Two major ICs - Radio IC CD2003GP and Audio OP Amp D2822A. These are all through hole parts.


the  other side

 b) New model

One side

You can find the PCB name is KK-2005KT.

This side has almost none on it except one potentiometer at center and two Al. Electrolytic Capacitors. No PVC (Poly Vari Con), no IFTs, no Ceramic Filters, no Air Coils, no Ceramic Disc Capacitors, nothing of these parts crowdedly placed previously. All of them gone away.

the other side

Three major ICs are found.

Radio IC KT0936M (18 pins)
Audio Amp IC  LPA8003S
LDO Regiator IC AMS1117-3.3V

Plus many chip resistors. All SMT parts.

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Old Model

7 SW bands: 5.67-6.43MHz, 6.96-7.87MHz, 9.28-10.36MHz, 11.15-12.28MHz, 13.15-14.00MHz, 14.90-15.80MHz, 17.06-17.90MHz

New Model
7 SW bands: 5.95-6.20MHz, 7.10-7.30MHz, 9.50-9.90MHz, 11.65-12.05MHz, 13.60-13.80MHz, 15.10-15.60MHz, 17.50-17.90MHz

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The reproduced sounds are noticeably different.

Old Model (1W 8 ohm Speaker) - so called 'analog sound' - soft, round and somewhat deep to my ears.

New Model (1W 8 ohm Speaker) - so called 'digital sound' - hard, edged and somewhat shallow to my ears but not uncomfortable.

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Weight

The new model is lighter than the old model due to much less component count.



sptt

China made Portable Mini Speakers

1. Blue Tooth Speaker

The sound is not necessary very good but it works including Blue Tooth function. The large IC (cannot be identified) in the center seems to do everything. The Audio Amp IC is 8002B.



2. Portable Speaker

The accordion (black one in between) enhances the sound - a good idea. So the sound is not very poor.

The input is a phone plug. The tiny Li-Ion Battery is connected to a USB connector to charge it but no charger IC found. It has an LED indicator for 'On'. It works anyway. The Audio Amp IC is CG4812. I cannot find the spec on the internet. I found the spec of similar number SGM4812 (package MSOP10).



3. Very simple Portable Speaker (inside)

This one is terrible not just its sound. The input is only one phone plug. Though I found a very tiny Li-Ion Battery no USB connector to charge it. So this is a disposal type of power from the charged battery. The battery is seriously damaged. It worked anyway. The Audio Amp IC is 8003.


sptt