Tuesday 26 October 2010

Poor Mans Antenna Analyser

mkiv_antenna_analyser

The poor mans antenna analyser was brought to my attention by Dave M0GGK. i had been looking for something like this for a long time.

It was designed by Andre, GM3VLB and his article is really interesting reading. He gives full details of how you can build one yourself. I have one built and am in the process of calibrating the meter.

I decided to buy one ready built from Andre and he still has a few more available but he says when they are gone, they are gone :-) he got the beautiful 50ua meters at a good price but there are no more available from that source.

I ordered one from him and it arrived a few days later, i must say it is beautifully made and is a great asset in my shack. Now i don’t have to rely on guess work anymore when building and setting up a new antenna.

check out Andre’s website http://www.gm3vlb.com/general/poor_mans_antenna_analyser.htm

Monday 25 October 2010

HB-1a 3 band QRP rig

hb-1a-2a

The HB-1a is a small 3 band QRP CW rig made in China. It was produced as a kit but today the HB-1A is offered as a complete product (batteries not included) using professional assembly with Surface Mounted Technology. The cost seems to be in line with most other rigs offering similar features, power output, multi-bands and of course, size. The current pricing including freight direct from the manufacturer represents a bargain when compared to other units offering similar features.

The digital display offers power output, RIT, storage frequencies as well as short-wave radio receiver functions.

This is an ideal transceiver for the CW enthusiast who likes to set up a station at impromptu locations. A picnic bench in a park with the antenna wire thrown in to the closest tree, a remote camp-site, long nature walks are just a few thoughts. The unit does not include an internal antenna tuner.

The current drain is of a low-power design and allows approximately 50-75 mA on receive. The manufacturer rates the unit, using 2200 mA rechargeable cells at 2 watts output power at 15-20 hours with receive and send ratio of 2:1.

I had to replace the 100 ohm trim pot in the driver stage on this one as it was broken. I set the output to 4 watts on 40m and it was also 4 watts on 30m, on 20m it was about 31/2 watts. The pa transistor is heat sinked against the case but it was standing in free air on this one so i fixed that, used a mica washer and plenty of heatsink paste.

Output seems fairly steady and got clean reports, my power meter is not very accurate so i think i’ll make new one!