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Chinese kits

This is mainly a list for my own reference about chinese QRP and other kits relating to hamradio.

Banggood.
Broadcast FM radio kit with Frequency counter
http://www.banggood.com/DIY-FM-Radio-Kit-Electronic-Learning-Suite-p-1017325.html
The frequency counter should be able to do 1-170MHz, 0.1MHz resolution.
Might make a start for a IF rig for some 10/24GHZ gunnplexer or DROplexer WBFM rig.

1-30MHz QRP atu kit.
http://www.banggood.com/QRP-1-30-Mhz-Manual-Antenna-Tuner-Tune-Kit-p-914663.html
Looks like 2x polyvaricon + 1x T50-2 or -6.

"45W" 3-30MHz HF linear kit.
http://www.banggood.com/DIY-45W-SSB-HF-Linear-Power-Amplifier-Amateur-Radio-Transceiver-Shortwave-Radio-Development-Board-Kit-p-1018834.html
No heatsink, 2x IRF530 fets in pushpull, 2SC1971 ( usually pulled from scrap) as driver and some SOT89, usually 2sc3357 transistor at input.
Regulator for Bias supply. Some dude got 1W @50MHz. Very high gain, tens of milliwatts input.
This is also available on ebay.
http://www.caarc.ca/wp-caarc/wp-content/uploads/2016/03/Banggood-IRF-530-PA-Instructions-V1.4-.pdf
http://www.caarc.ca/news/hf-pa-amplifier-kit-instructions-decrypted-from-chinese

40m CW transceiver 1.8W "WAMING  5"
http://www.banggood.com/Frogs-DIY-Calling-QRP1_8W-Kit-CW-Receiver-Transmitter-7_023MHz-p-991194.html
7.023MHz crystal, Traditional SA602+LM386 RX, no volume control, adjustable RIT

40m Pixie2 kit, no RF connectors
http://www.banggood.com/DIY-QRP-Pixie-Kit-CW-Receiver-Transmitter-7_023MHz-Shortwave-Radio-p-991566.html
Mostly Pixie2 with 7.023MHz crystal. Antenna and PSU connection via similar connectors. Adjustable RIT

40m Pixie2 kit, BNC antenna connector
http://www.banggood.com/DIY-Radio-40M-CW-Shortwave-Transmitter-Kit-Receiver-7_023-7_026MHz-p-973111.html
Mostly Pixie2 with 7.023MHz crystal. BNC antenna connector. Adjustable RIT. Typical DC barrel for PSU.
I have built one of these for 40m and it works. A metallic case does make a difference in the noise floor.
Feed it with a battery as mains hum easily breaks thru in other cases.

Frog Sounds 40m CW transceiver 2.6W
http://www.banggood.com/Frog-Sounds-HAM-Radio-QRP-Kit-Telegraph-CW-Transceiver-Receiver-Radio-Station-p-980512.html
Got one of these in the works. Typical SA602+LM386 RX, Variable RIT. RF attenuator with 5k pot for volume control and dealing with strong signals.
One 7.023MHz crystal used as a frontend filter for the SA602. But it is not matched in anyway. I'm planing on replacing it with a 7.020MHz muRata filter from my junkbox, it has 300ohm impedances which add their own problems. Mine still needs some debugging as it does not work properly. The black soldermask on the pcb makes following traces hard. 

"L4 is 11 turns (about 20 cm of wire) on T37-43 (black) and L5 in 16 turns (about 30 cm of wire) on T37-2 (red) 6) LED: the short lead is the green, middle lead is the red, and the longest (middle) lead is the common anode 7)"

Forty-9erV1.1
https://www.aliexpress.com/item/Assembled-Forty-9er-3W-HAM-Radio-QRP-CW-Shortwave-Radio-Transmitter-Receive-Factory-in-Stock/32734299343.html
2SD882 as PA device, it's an audio transistor with crpa gain on HF, 8050 as predriver, I selected the one with the largest HF for this. 
Problems: 220k resistor instead of 1Mohm, one 100nF cap too little. 
The included instructions ware a crappy quality xerox. Use the below pdf instead.
http://lz1lcd.spirka.net/manuals/Forty-9erV1.0.pdf

This is easier to construct than Frog Sounds V3 as you can see the pcb traces underneath the red soldermask, unlike with the black soldermask. 
Same instructiosn with toroid coil as with Frog Sounds: 
 "L4 is 11 turns (about 20 cm of wire) on T37-43 (black) and L5 in 16 turns (about 30 cm of wire) on T37-2 (red) 6) LED: the short lead is the green, middle lead is the red, and the longest (middle) lead is the common anode 7)"

One of the cases I have in my stash fits this quite well, it's just a tad too long so the exact installation of the kit might have to wait. I'd also like to brink the RIT out front, and would also like to have more frequency agility, like a 7.040MHz xtla in addition to the 7.023MHz one. 

The PA device is an 2SD882 from NEC without a heatsink.
http://www.st.com/content/ccc/resource/technical/document/datasheet/94/f8/66/07/d9/c8/40/55/CD00062867.pdf/files/CD00062867.pdf/jcr:content/translations/en.CD00062867.pdf

I'm tempted to replace it with something else. the long case would allow even weird substitutions.
Like 2N6080 as I have many of those and it's a real RF transistor might not be terribly stable.  
https://www.rf-microwave.com/datasheets/6676_STMicroelectronics_2N6082_01.pdf

The "NE602AN" used is a blacktopped part. 

Manual tuning aviation receiver.
http://www.banggood.com/DIY-Aviation-Band-Receiver-Kit-High-Sensitivity-p-990306.html
AM VHF receiver, has squelch. Could be modified for 2m AM RX if wanted I guess.
I have one of these with pcb inductors. Yet to test it or modify it. Got it prebuilt for 2eur on a hamfest.

http://kc9on.com/ham-radio/qrp-radios/chinese-qrp-kits/

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