If you search on eBay for Ham Radio Receiver Kit you will most likely find a 40, 30, or 20 meter receiver kit by Ramsey Electronics. You might also see an 80 version of these receivers but it does not seem to be as popular. In fact you will probable find more then one of all three up for bid at any one time. A search at 0909 on 02/23/2007 revealed there were 4 Ramsey receivers up for bid.
For the purpose of this post only the HF single band receivers will be considered. The 10, 6, 2, 1.36and .68 meter receivers are super heterodyne and FM receivers.
Using the same information in the advanced search, under Completed listings only, eBay showed 9 with two 20 meter receivers having sold and one sold for $36.00 and the other went for $34.99.
Why do these little units not sell? They come with all the hardware and case. They have an instruction manual that is very complete with a check off list for each part as you install it. They are simple enough to build. So the real question is how do they perform?
You can not expect a receiver that retail for under $40.00 USD to be a top of the line receiver but to barely be able to hear a signal of 50 μv is unacceptable. Maybe this is why they are not selling.
5 μv is nothing to shout about but it is on par with other autodyne (otherwise known as direct conversion) receivers. That is about what you will get with with the Ramsey HF receiver is you make one simple modification otherwise you are stuck with the 50 μv sensitivity.
If you or someone you know has one of these radios and has found L1 does not peak when aliening the receiver that is because there is an error in the design of the PC board. The manual for the HR30 can bee seen at http://www.ramseyelectronics.com/downloads/manuals/HR30.pdf . Scroll down to page 10 and you will see a diagram of the PC board. On the front of the PC board (that is the top in the photo) there is a square marked as L1. Looking at the coil at the top closest to L2 there is a solder pad that goes nowhere.
L1 is called a coil but it is actually a transformer. The input comes from R1, RF gain control, and the output goes to the input onU1, the RF amplifier, detector and BFO. The solder pad which was pointed out above is the other side of the input coil (transformer) L1. The reason this is left open is to make a lose couple on the front end of the receiver and the antenna. The problem is the receiver is not sensitive enough to work well with a loosely coupled input. Running a jumper wire from the solder pad to ground will raise the sensitivity of this unit about 20 dbs. I have done this same modifications to the 40 and 20 meter versions and the results were about the same.
These radios run on a 9 volt battery. Owners may be tempted to place a connecter on the back and connect them to a 12 volt power supply. The unit should be able to withstand the voltage but it would be recommended they ad a 10 volt regulator inside the unit to protect it. There is plenty of room. They will probable have to add some choke coils at t he input because autodyne receivers have a bad tendency to pick up AC and it can prove to be very difficult to keep out.
While I would not call these great units over all I would say these receivers are not a bad unit for the price. For the new kit builder they do give a very easy unit to construct and take pride in.
If you or someone you know has had experience with these units or any other Ramsey Electronics kits please send me an email at firstname.lastname@example.org (be sure to add the words Ham’s Life to the subject line so the spam monster will not eat it) and let me know your experience and opinion.