Monday, October 05, 2009

New arrival from China

A knock on the door this afternoon heralded the arrival of my latest QRP radio - an HB-1A 3-band (40/30/20m) CW transceiver from China.

Shipment had taken just over a week and, unlike products ordered from the USA, there was no customs charge or VAT to pay, so the radio cost me a total of £165.

Opening the box revealed the radio extremely well packed in expanded polystyrene, plus a photo-printed card with a picture of BG2FX in his lab - presumably the builder. There was no manual, but the eBay listing had linked to an English language manual in PDF form that I could print out.

The radio itself seems very well made, the impression of solidity created by the heavy steel case which is well-painted in a black crackle finish. As this is intended to be a portable radio, an aluminium case would have saved a bit of weight.

Unscrewing two screws and removing the bottom of the case revealed a bit of a surprise - the two 4 x AA cell battery holders were not connected together or to the plug that connects them to the circuit board. I will have to solder together and insulate the wires myself. Four rubber stick-on feet were also inside the case, which I fitted to the bottom of the case before reattaching it.

Applying 12V DC from my shack power supply I was pleased to find that the HB-1A worked perfectly. There is no loudspeaker, output is headphones only, and best results were obtained using a pair of MP3 player style ear buds. The receiver is no match for a K2, but it is quite lively. Selectivity is reasonable and adjustable in three steps - 900Hz, 700Hz and 400Hz for CW - but stopband performance is quite poor: I could hear strong CW signals a few kHz away.

Although this is a CW-only transceiver it can receive LSB and USB as well. Tuning is continuous from below 40m to above 20m so you can even receive shortwave broadcasters by zero-beating the carrier. There is no bandswitch, but the HB-1A has 20 programmable memories which are pre-loaded with useful frequencies in each band such as the QRP CW frequencies - and the broadcast frequencies of Radio China!

The front panel key jack can accept either a straight key or a paddle. This is detected at power-on. However, for a straight key to be detected the center contact of the stereo jack must be grounded. Other radios I have go into continuous key-down unless this contact is open-circuited. Why can't there be a standard?

I was pleased to see that I got a genuine 5W output for 12V DC input. At 9V DC I measured 3W output. I haven't tried batteries yet as I have not yet wired up the internal battery holders.

The battery holders are a tight fit between components on the circuit board and there is no facility for charging rechargeable cells whilst they are installed. I will find removing the bottom of the case, removing the batteries to recharge them and then reinstalling them a bit of a nuisance, so I will be looking to install a socket so that they can be charged in situ.

Despite calling CQ on both 20m and 40m I haven't managed to have any contacts yet - I guess conditions aren't all that good right now.

With a power consumption less than half that of the FT-817 the HB-1A should give decent battery endurance on a set of rechargeable NiMH cells. This is going to be used as a portable HF rig, so the search is on for a small and equally robust Morse key for it. I'm trying to think how I can adapt the DinKey - which turned out to be such a disappointment when used with the FT-817 - so it can be plugged in to the 3.5mm key socket of the HB-1A.

That's all I have to say about this little Chinese radio for now, but I'm sure you'll be hearing more about it once I get everything set up for operation in the field - assuming that the weather plays ball!

7 comments:

Paul said...

Hello Julian, congrats with your new and tiny transceiver. It looks very nice and solid. Lets us know how you experiences are. 73, Paul PC4T

Steve GW7AAV said...

Hi Julian,
Looks like a load of fun. Hope it exceeds your expectations. Early days yet but the other reveiws I have seen had only a few little niggles but the buyers were in the main happy with their purchase. I wonder what homework you did before buying it as all the other reviewers I read mentioned the none-fitted battery holder and feet. I guess it lets you leave out the battery option or fit a different battery such as a PP3 9v or maybe a rechargable Lithium Polymer or something similar. I heard someone say the next version will do ssb but not found anything on the net about it.
Seems like a bargain at that price I would expect a kit.

Regards Steve GW7AAV

g4ilo said...

Steve (and others.) I have just joined a Yahoo group about this radio, and last night someone posted a link to buy a kit version: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=270466025511&ssPageName=STRK:MESE:IT

The PCB in mine is mostly SMT parts, and I don't know what the instructions are like - probably not up to Elecraft standards - so even though I've built a K2 and many smaller kits successfully I'm not sure I would have been brave enough to choose the kit option for this one.

KemGeo said...

Hello,
can someone help me to find adress where I can buy or order the HB-1A please.
Best regards, ON6JK
mail: gkempenaers@skynet.be

g4ilo said...

They are sold on eBay. Just log on to eBay and search for HB-1A. However I think there is no stock at the moment. For more info see the HB-1A Yahoo group.

JimmyBahia said...

In regards to the dc power cord, what size plug size fits best?
(2.1mm,2.5mm,etc.)

g4ilo said...

Good question Jimmy. I used one of several that I happen to have in my junk box. I think they might be 2.5mm.