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Old 29th Mar 2019, 3:05 pm   #131
Tully Bascombe
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Join Date: Mar 2019
Location: Chesterfield, Derbyshire, UK.
Posts: 24
Default Re: More Chinese AM radio kits

For the last year or so I've been steadily working my way through these cheap Chinese kits. At the moment my collection consists of:

FM Alarm Clock Radio with LCD display. Works OK except very tricky to tune without distortion due to stiff tuning knob. Frequency indication is almost correct. Clock keeps good time.

ZX921. If it wasn't for the whistling, howling and motorboating this might actually be a good sensitive radio. Once tuned in, volume level and sound quality is very acceptable.

HX108-2. Have built two of these. With the first one I messed up and got an output transistor the wrong way round which explained the awful distortion. After correcting my mistake the sound quality was no better so maybe the transistor was fried. The second one had a damaged speaker so I swapped it with the other one. Works quite well but sound quality still not great.

S66E. Have built three but only paid for one (long story). All work surprisingly well and sound is better than expected from the plastic speaker. Headphone socket is a bonus although the hole in the case doesn't line up with the PCB. As an experiment I built one of them with closer tolerance resistors and caps. Result: no noticeable difference.

210SP 'Paeansonic'. Good FM performance but AM very weak. Stiff tuning due to the horrible dial pointer method. Locks onto FM stations well, clean, clear sound from the tiny plastic speaker. Awkward to tweak as the batteries come out when you take the back off.

ZX2051. As with the 210SP, good FM performance but weak AM. LED tuning indicator actually works. The real speaker gives it an advantage.

ZX620 AM/FM in an ugly yellow case. The actual radio I received from Banggood was the AM/SW version ZX623 and got a full refund. SW is one band 15M, not very useful. AM performance is excellent as is the sound quality from the 'large' real speaker. I can quite happily live with this one, just a shame that's there's no FM. It appears that the ZX620 is no longer available.

Next on my list is the multiband EDT-2902 which could possible be a bit of a challenge.
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