The Basics that will get you through

[toshiba1]

In an ideal world and finance permitting, and going by the high standards set by many here and (with the ultimate respect to Albert) How many London stations follow through with, High performance Audio processing compressors and more compressors and eqs. I am sure some of the rigs if not most forgetting the Chinese sprog boxes. are built to high standards in London with built in, RDS, limiters MPX etc. But truly is it realistic to achieve, studio sets ups as posh as some i have seen on here that are abroad where different rules are more select and relaxed regarding pirates, if you are an illegal broadcasting in the UK.

What is the most basic set up you could have, if keeping out of the red, and assume antenna is a good match and rig is not sprogging. What else is basic essentials, that you could get away with when things have to be considered dispensable and the cost involved is generally high to replace?

Additional... What could you buy off ebay right now that would be useful getting you started right, as i see lots of stuff on there from limiters, 1 Watt jobs, encoders, power amplifiers etc.

[FourierFun]

I think I get where you're going with your question, because I'm going down the same route right now. I want a clean signal with good audio quality (while leaning some stuff at the same time). At the same time I have other hobbies and interests all vying for my spare cash so I have to work within some guidelines. For me, I wanted to find a "good" exciter (in terms of signal quality) in the budget I was willing to spend and I worked out from there. There were several options I looked at: Two different radio shops in The Netherlands had several options, there were the PIRA designs, and then several right here on these forums. It was tough to choose but my first project is the 1w FM from Reverend here on the forums. I opted with v3.07k. After I get that built, my next rig is going to be the "One Last FM Exciter" on here by zozo. Sinus Trouble has several cool projects here including an RDS encoder that I want to try after that.

I guess my point in all my ramblings is that ebay isn't the end all, be all for gear. Everything I've been able to find on ebay (with the exception of a stereo limiter/compressor that tickled my fancy) I can find from shops dedicated to RF for the same or cheaper prices because they don't have to pay ebay's extortion fees. Whether or not these will meet the quality standards you're looking for, I'll let others with more experience chime in.

In any event, I'd really check out the offerings available right here on the forum to start.

[yellowbeard]

Ebay is a pig in a poke, it's riddled with absolute shite with the odd nugget of good stuff sticking out of it like sweetcorn. I have learned not to trust it at all. Dutch stuff is your best bet, I have 2 Dutch RF shop 6 Watts here waiting to build and 2 more out in the world, they're clean and easy and look swanky with the blue LCD screen on them.

[toshiba1]

I think I get where you're going with your question, because I'm going down the same route right now. I want a clean signal with good audio quality (while leaning some stuff at the same time). At the same time I have other hobbies and interests all vying for my spare cash so I have to work within some guidelines. For me, I wanted to find a "good" exciter (in terms of signal quality) in the budget I was willing to spend and I worked out from there. There were several options I looked at: Two different radio shops in The Netherlands had several options, there were the PIRA designs, and then several right here on these forums. It was tough to choose but my first project is the 1w FM from Reverend here on the forums. I opted with v3.07k. After I get that built, my next rig is going to be the "One Last FM Exciter" on here by zozo. Sinus Trouble has several cool projects here including an RDS encoder that I want to try after that.

I guess my point in all my ramblings is that ebay isn't the end all, be all for gear. Everything I've been able to find on ebay (with the exception of a stereo limiter/compressor that tickled my fancy) I can find from shops dedicated to RF for the same or cheaper prices because they don't have to pay ebay's extortion fees. Whether or not these will meet the quality standards you're looking for, I'll let others with more experience chime in.

In any event, I'd really check out the offerings available right here on the forum to start.

Nice one Fourierfun, I have noted Reverends builds and noticed on completion sales some had been offered up. I have an nrg 4 watt sort of still in the build stage, not sure how long its been since i went back to it to finish. I am not really a tech guy, i have soldering skills and elementary understanding of some basic electronics, but I do not have spectrum analyzer, oscilloscopes, so a 4 watt is probably my level of capability maybe?

I was not expecting much in the way of positive opinion on the quality from eBay as most of the gear is garbage. I mean at 10 bucks for a 0.5 watt pll its got to be, right? I just wondered if you had too buy from there, what people might go for. I actually have a decent 100 watt rig but its bulky 240v and not for any use here. Hence posts about in the field on low power previously.

As far as sound goes though, it does seem a minefield and costly way, if you go by some of the advice i have read, as much as its golden, its just far to expensive to implement. We only ever had a compressor with some mild settings and light limiting in the chain and some after EQ. Now it seems that is jut not enough.

[toshiba1]

it's riddled with absolute shite with the odd nugget of good stuff sticking out of it like sweetcorn

that did make me laugh yellowbeard. Fairplay lol

[FourierFun]

Nice one Fourierfun, I have noted Reverends builds and noticed on completion sales some had been offered up. I have an nrg 4 watt sort of still in the build stage, not sure how long its been since i went back to it to finish. I am not really a tech guy, i have soldering skills and elementary understanding of some basic electronics, but I do not have spectrum analyzer, oscilloscopes, so a 4 watt is probably my level of capability maybe?

I wouldn't let the lack of some tools hold you back. A (quality) spectrum analyzer is over a grand easy. I don't own one of that caliber, so I rely on people like Albert H and others to guide me on what is "good" in terms of signal quality and what isn't. One of the reasons I went with Rev (aside from the price/performance ratio) is the relative lack of tools needed to get going. Though I own a scope and some other tools, based on his instructions a quality multimeter is all you need to get his kits going. Design philosophy and proof of concept data, not output power, determines what you need in terms of tools IMO.

I was not expecting much in the way of positive opinion on the quality from eBay as most of the gear is garbage. I mean at 10 bucks for a 0.5 watt pll its got to be, right?

Whether or not its "garbage" really comes down to intended use. If you're looking to boost that 500mw signal coming from the amplifier on that cheap board using a BH1417, you may not be satisfied with the results in terms of signal purity and/or audio quality. However, if you just want to use it to play radio DJ for your garden and immediate neighbours, it might fit the bill. I actually have several of those BH1417 kits (some I assembled myself and some were SMD pre-assembled) and for what they are they're quite fun to play with for the price. That being said, there is definitely room for improvement on the audio side, and if its like the BH1415 boards in terms of reported signal purity from various sources, I don't know how much I would want to amplify it.

I just wondered if you had too buy from there, what people might go for. I actually have a decent 100 watt rig but its bulky 240v and not for any use here. Hence posts about in the field on low power previously.

As yellowbeard said, I wouldn't. Too much out there from the Dutch as well as reputable RF-geared shops that make me steer clear unless it was something I absolutely couldn't find somewhere else.

[toshiba1]

I wouldn't let the lack of some tools hold you back. A (quality) spectrum analyzer is over a grand easy. I don't own one of that caliber, so I rely on people like Albert H and others to guide me on what is "good" in terms of signal quality and what isn't. One of the reasons I went with Rev (aside from the price/performance ratio) is the relative lack of tools needed to get going. Though I own a scope and some other tools, based on his instructions a quality multimeter is all you need to get his kits going. Design philosophy and proof of concept data, not output power, determines what you need in terms of tools IMO.

[Albert H]

As I pointed out before, if you can't afford a Spectrum Analyser, you can get pretty good results with a simple home made Absorption Wavemeter. If anyone wants some suggestions on building one, I can put some diagrams up here.

Also, audio processing doesn't have to be too expensive - as a first, simple approach, you could buy a secondhand Behringer Compressor / Limiter for not too much money. You could also build a simple clipper (to prevent overshoots), and if it's set up sensibly it'll be virtually inaudible in use. Again - if anyone's interested, I can put up some suggested circuits.

There was a simple fast attack / slow decay limiter in the Philips NE570 databook. This IC is still widely available, and with an LM339 comparator, it's quite easy to build a basic audio limiter - again I'll put up the circuit diagram and a suggested PCB layout (and Veroboard layout if anyone still uses it).

With a bit of effort and perseverance, you can build some pretty good equipment for not a lot of money....

[radium98]

Albert , sorry for my ignorance , but how would an Absorption Wavemeter? griddipmeter , replace or nearly replace a spectrum , or even how would you know that there is no more harmonics ?
i know nothing replace a narrow bandwith spectrum visually , but the idea of that grid dip meter amased me .

[toshiba1]

As I pointed out before, if you can't afford a Spectrum Analyser, you can get pretty good results with a simple home made Absorption Wavemeter. If anyone wants some suggestions on building one, I can put some diagrams up here.

With a bit of effort and perseverance, you can build some pretty good equipment for not a lot of money....

Thanks Albert appreciate all the info there. Is there any software that can do the trick? With eternal probes, I'm sure i saw something like this sometime back but could be getting mixed up. I imagine it would be only to test low power if that is the case?

What about this... Don't shoot me lol. https://www.ebay.co.uk/itm/314125410409 ... R5T7p7LgYA

[yellowbeard]

Practical Wireless did a review of that speccy analyser back in July, they found it to be a bit fragile mechanically but quite good at the actual measurements. I am gonna get one, I have access to my mates analyser, but that usually degenerates into smoke, drink and a taxi home.

[radium98]

tinysa but the bandwidth is poor . how do you see noise hum or buz in the carrier . But not bad for visual things , i ask again how the grid dip meter can be used as a spectrum nearly ?

[Albert H]

Nope. The grid dip (actually usually a Gate Dip Meter these days) is used to detect resonance, and can be used to match aerials as well.

The Wavemeter is a passive device, using a tuned circuit (usually with pretty high "Q") through a germanium diode to move a sensitive moving coil meter. It will clearly indicate the main carrier frequency, and as you tune it, will indicate harmonic content. Look it up!

[radium98]

albert , i was thinking they were the same things , so can you post a wavemeter circuit s you said before , thanks .

[toshiba1]

Practical Wireless did a review of that speccy analyser back in July, they found it to be a bit fragile mechanically but quite good at the actual measurements. I am gonna get one, I have access to my mates analyser, but that usually degenerates into smoke, drink and a taxi home.

Well that's me sold on one then, i'm thinking about also getting the antenna analyzer too.

https://www.youtube.com/watch?v=QJYeFpiqY8c