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It has a tubed audio output stage, probably a single twin-triode for left and right in one tube. There are no valve RF stages in it. Valve RF stages can have real advantages# for today's conditions. Solid state tuners built so as to have those advantages are around. # Ask? Jolida is not an 'RF / FM expert company' and will have used application notes for someone else's chips. Being SS, at least it won't need to be driven quite so hard by the antenna as most valve tuners would. When considering FM we need to have a good grasp of what antenna set-up might be needed to match up to the desired stations' power, distances and bearings - as part of the package, and at the same time. You are building a radio based music reception system, and the antenna is an integral part of the results you'll hear. In your situation a good enough antenna (lots of gain), and mast, and rotator - can approach the cost of the tuner. You may also have then decided to buy a tuner with selectable RF bandwidths. Reception in the country - can - be simpler in the sense that one antenna or direction may be able to cover several transmitters in a given town. You will need a directional antenna with gain, to get at all close to the tuner's music potential. And you will need more antenna gain than most people do - longer and thus heavier and a higher wind load - and a stronger mast. If you go with one antenna and a rotator the set-up has to be good enough for your most difficult station. FM is dependent on line of sight reception, especially stereo. Physics. There just might be a far cheaper, and far better performing, DIY alternative - to the cost of a long boom yagi, rotator and mast. BUT - without your own research effort you won't know if it is feasible for where you are. In any case, this information* will also be vital with a rotator set-up anyway. *? Map the station's transmitter's bearings onto your 'house and block' plans with North marked on it. Someone who approved your house has them, at least. Only then you can determine how many stations are on bearings within say plus or minus 15 degrees from your home. Then read the 'rhombic-wire DIY FM antenna' article, which you will have from me, after you've emailed me. They are directional - and even when sized for indoor use on a ceiling for FM wavelengths - can be very effective. Let's say you have one town with >1 station about 20-30 miles away, and you aim a 'doubled spread rhombic' at it with good gain and a fairly wide reception angle (beam-width). Now, what if there was a more distant and weak college station - worth bothering with - but close in frequency to a station in that town, and close (say 20 degrees) to that first antenna's axis. You could add another rhombic with a narrower beam-width, and switch to that antenna to listen to that station, and get good clear reception, because you have effectively nulled out the other station in the RF mix coming down into the tuner. OR connect the town antenna out of phase to the 'single station rhombic' giving even better nulling. Your single rotatable Yagi is unlikely to be as good, for such a job. Large outdoor rhombics were used to communicate with the Apollo missions. As each of the four equal sides begin to approach one wavelength of a transmitted frequency a rhombic has 6db of gain, a twin has 12db. A single wire item with sides 12 feet long, still suitable for many room's ceilings, will have 6db of gain at 88 mhz, and about 7.4db at 108mhz. Making it from twin ribbon (300 ohm antenna cable?) will double the gain. While not physically exhausting there is a fair amount of work, and a lot of preparatory research for this option. OTOH your reception is likely to be far better, and for far less money. Your own time budget is a factor. Compared to getting reception nailed, tube-rolling is a very low-order issue. Along with interconnects and power cords. To sum up, the message for anyone who wants the best results from a given investment in FM, is to treat FM as a radio system and research the reception issues that exist where you are. ;-) Simple, really!
Warmest
Timothy Bailey
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
http://www.theanalogdept.com/tim_bailey.htm
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