Posted by Fernando Duarte on 10th Nov 2012
The RX340 is, like most professional ones, rarely encountered. But he is one of the few professional tools that meets the needs of shortwave listeners. So, thanks to the "DSP", a notch filter, the band-pass tuning and a noise blanker available. The mechanical stability is good, wherein the front panel is covered with a self-adhesive film, on which the label is printed. Comparing this with the front of a Telefunken or Racal device, this is a very cheap and sensitive surface. But that was the grossest gaffe of RX340. Has the quality of reception for it in yourself! The RX340 can really convince. The receiver is hard and so high signal-noise, so that one begins to rave. However, in order to exploit the full potential, it must be driven with the RX340 manual receive reinforcement. Only we get the receipt results deal a feeling of surprise.
I have compared it. RDR50B with Reuter, the Telefunken E1501 & E1700 The sensitivity of the RX340 is moderately related to the amount of the Telefunken devices. With the weakest signals to the turf, the Telefunken devices have the nose a little bit ahead because of its very bright playback. But they sound much more! The RDR50B falls in this discipline from something. Signals to the grass is not his forte. For the shortwave listener the synchronous detector (SAM) is an important function. This allows a fading largely outdoor listening pleasure. Unfortunately, the RX340 makes a small mistake here! The synchronous detector to quickly loses synchronization when the signal is weaker. If the signal is above a certain value, the effect of the synchronous detector is peak. Absolutely clean reception. Noticeable is that the noise blanker is not in SAM works. I suspect this is not well written. Incomprehensible, the notch filter is not available in AM. In SSB, but all functions are available. Which also contributes to a peak reception is the programmable AGC. These can be freely adjusted in the rise time, hold time, and in the fall time. Something is quite rare. The memory management is simple and effective. The instructions had to be taken not to hand.
The bottom line may be said that the RX340 can compete with any other device! The reception quality is largely unmatched. Only the latest generation SDR devices could perhaps be a touch better and more flexible. But, these are not stand-alone devices.
A dream receiver the RX340!
Posted by Fernando Duarte on 24th Oct 2012
I have the RX340 now a lot of weeks and can say that this Receiver are one of the best that I have purchased. But it are not perfect!Only one two things are not so good. The SAM are poor for this High End SW Receiver. By weak Signals it lose to fast the Synchronisaton. In AM and SAM if the AGC are Fast or Medium, the Sound have sometimes clicks. I think this come from the DSP. Very poor is, that the Notch Filter don't work on AM and SAM. Not acceptable for a High Class Receiver in this Price Range.
The rest I can give only positive Feedbacks. For weakest Signals are the RX340 an excellent Receiver. If you work with the Manual Gain, they get a Reception almost without noise. Sensivity and Selectivity are nearly perfect.
Posted by John Adams VK2XCQ on 1st Jun 2012
The RX-340 is a special receiver.
It can dig out a weak signal and can handle the local 200KW AM station without melting. Its strength and weakness is its flexibility, you need to understand what you are trying to do, to get the best from the 340. It is not for the beginner, it comes with no setting, it is up to you to work them out. If you spend the time it will reward you with excellent reception.
I have many high end receivers, each has its own special area that makes it better than the others. The 340 is different it is very good in most areas, so it kind of wins against all the others. The 340 has the best received signal clarity of every radio I have ever listened to, what they send is what you get, no colouring at all to the audio. It blows away any thing I have heard for clarity. I can say that as a fact, if it is being sent in the transmission you will be able to hear it (as long as you have set your 340 correctly).
RFI from the display is almost nil, you need to place a am radio 6 inches from the VFD before it is effected, and the rest of the box is RFI silent, excellent internal shielding really helps, this is great for a crowded desk. You try to use a AM radio any where near a SDR based radio or other LCD monitor display, all you get is the RFI from the display and or something from the hardware.
Best of all it is a standalone unit, it does not need external computers or the internet to work, its software works, it is a rock solid box and mine has a nice thin wooden cover that looks nice and homely.
The antenna needs to be good, just like any receiver, the better the antenna the better the reception.
The Noise Blanker works on pulse noise, but not on other types of noise.
My wish list that would make the 340 nearly perfect:
It would be nice to have it work into the UHF bands.
A noise reduction option.
A self tracking heterodyne notch filter that works in all bandwidths and modes option.
12v power option.
A stepdown of the first IF output to 10MHz,so I can connect an external bandscope.
An external bandscope option , like the one from elecraft.
Oh Yea, if you do get a 340 , turn down the RF gain between 20 to 30.
Hope this helps you decide to buy a RX-340.