Who makes these?

[shuffy]

multiband process audio, add pre-emphasis and generate the outputs MPX with RDS signal, but leave out the serious RF and PLL part

They are designed for listening to your mp3 player in the car - not for broadcast applications.

[FMEnjoyer]

Even the QN8007 (supposedly the best of them) puts out as much energy in spurious crap as it does in the actually intended carrier.

A simple four transistor, two IC exciter can be clean and stable and cost just a few pounds to build. ½W is really easy to achieve with cheap components, but proper calibration requires use of a real spectrum analyser - NOT one of those toy VNAs!

And yet Spectraman shows a couple of the chips when amplified is not sprogging on the Youtube video.



And such few pounds, PLL, perfectly clean,stereo, 500mW rigs are not available anywhere at all just like rocking horse shit.

You know very much and are very helpful usually Albert, but this is no help to anyone at all.

All his videos if interested, if it is bad he says so, does not tar everything with the same brush.

https://www.youtube.com/@spectra-man/videos

It is all rather pointless anyway, do some other hobby, less risky and time better spent.

[yellowbeard]

And here is a video of the mythbusters polishing a turd:



This is getting heated, we don't believe the youtuber and you do, so you buy that gear and we won't. Game over.

[EFR]

Gotta order one and wake up my CRTU-RU....

Then we dont need to fight, I think its good enough for this measurement?

[EFR]

If everything goes well, there is one at my desk on monday evening or at tuesday morning.

[FMEnjoyer]

This is getting heated, we don't believe the youtuber and you do, so you buy that gear and we won't. Game over.

Yet you are promoting these better off in the bin kits on this thread ?

viewtopic.php?t=3622&sid=5804322e51eb87 ... b2f210be27

I am very relaxed here cause I have no horse in the race, just interested and looking at facts.

Where are the Euro/UK 7 Watt, Frequency stable, LCD, stereo, continuously variable power, low enough harmonics and spurious rigs, boxed, with connectors and a user interface that is not dip switches for £70.00 ?

Oh that's right... they don't exist.

You have to pretty much be off your nut to run an FM pirate station in 2025 anyway FM pirates are about as much use as indicators on a Mercedes. Tested on RIGOL and Bird, not exactly rubbish test equipment there 17:10 in the video for harmonic and a distinct and total lack of spurious in between.

[yellowbeard]

I stand by that post you quote, I don't believe the guy on youtube and I have better things to do.

[Albert H]

Exactly right YB - the "tests" shown on the Youtube video are bogus.

[FMEnjoyer]

Spectraman is on this forum for start under Ogre Vorbis I think. Why would he make bogus tests on a video? That claim has zero credibilty.

What sounds a bit bogus is saying the above GD2007 is bogus and then in other post promoting some Dutch VFO rubbish as sm,ething worth having.

Not to mention he calls out all the bad chips clearly for everyone to see with their own eyeballs.

He sounds American to me

https://www.youtube.com/@spectra-man

And gives everything he tests a fairly honest review saying if the audio or spurious are abominations / is bad etc.

I wnat to deal with facts so don't shoot the messenger please.

No one should by a Dutch free running oscillator kit that in the end is a massively inconvenient PCB. Better a Chinese rig on a spectrum analyser with the QN8007 / QN 8066 or BH1414K than a VFO PCB kit.... I think.
I appreciate you try and protect your market, that's understandable. That should be done by product availability, quality and features, not baseless claims surely ? The only game over I suspect will be for Euro/UK made rigs soon so I can understand your being upset.

Certain UK decisions in 2016 certainly did not help the Dutch exporting quality PLL radio kit to the UK, their biggest external market, which I recall you were well up for Albert. Who would have guessed that it would a total disaster for trade.
Chinese stuff is getting better and people are getting worried for good reason I think.
I could not give a hoot as I am not buying any of it.

[oazz]

On the BH1414K chip.

[shuffy]

Where are the Euro/UK 7 Watt, Frequency stable, LCD, stereo, continuously variable power, low enough harmonics and spurious rigs, boxed, with connectors and a user interface that is not dip switches for £70.00 ?

I think with all these things, intended purpose plays a part. I can see a market for a small stereo TX which will cover your house and has a nice UI which will allow you to easily set/move frequency and change other parameters. Some of these China chips support this pretty well.

Then you've got the market for components of a broadcast chain where you don't necessarily want stereo/processing/RDS on the exciter board. Everyone has a different concept for their overall architecture. You want your exciter to be quite a low level block, you set the frequency once and cleanly drive your PA. So this is something like your DRFS board, or something bespoke. That's probably a smaller market than the first one?

To my mind the China chip TX doesn't satisfy the second requirement, not just on the quality front but on the deluge of other features that you just don't want - even if the thing was clean enough!

I've had a quick look and it looks like PCS are still selling something which is somewhere between the two, please someone correct me if I'm wrong but I don't see anything which looks like a BH/Q chip on their cheaper boards but I could be wrong since there's a fair bit of DSP stuff going on.

about as much use as indicators on a Mercedes

Right with you on that one.

[FMEnjoyer]

Where are the Euro/UK 7 Watt, Frequency stable, LCD, stereo, continuously variable power, low enough harmonics and spurious rigs, boxed, with connectors and a user interface that is not dip switches for £70.00 ?

I think with all these things, intended purpose plays a part. I can see a market for a small stereo TX which will cover your house and has a nice UI which will allow you to easily set/move frequency and change other parameters. Some of these China chips support this pretty well.

Then you've got the market for components of a broadcast chain where you don't necessarily want stereo/processing/RDS on the exciter board. Everyone has a different concept for their overall architecture. You want your exciter to be quite a low level block, you set the frequency once and cleanly drive your PA. So this is something like your DRFS board, or something bespoke. That's probably a smaller market than the first one?

To my mind the China chip TX doesn't satisfy the second requirement, not just on the quality front but on the deluge of other features that you just don't want - even if the thing was clean enough!

I've had a quick look and it looks like PCS are still selling something which is somewhere between the two, please someone correct me if I'm wrong but I don't see anything which looks like a BH/Q chip on their cheaper boards but I could be wrong since there's a fair bit of DSP stuff going on.

about as much use as indicators on a Mercedes

Right with you on that one.

Good post Shuffy.

PCS cost a fortune to import into UK, there basic add ons that should be included are triple the price they should be, they look to be PLL as you say + courier fees, import duty, VAT and other potentially unknown costs. and we have Brexit to directly thank for that. It is all surface mount, the same as Chinese in this regard and unrepairable by end user in 99pct of cases and at the end of the day it is still an ugly PCB and needs a 2 volt audio signal to drive, almost unusable.

Added feature are not a problem, sprogs and spurious are more so. The point being buy with care and you get a somewhat cleaner rig QN8007, QN8066, BK1414K seems to be the better ones.

I am not saying the decent of the Chinese rigs are the best rigs in the world, but they absolutely ARE getting better and FAST. And I would like Euro UK rigs to be more than they are, they are behind the times it is not 1989 now, even though a rig can still be good in 89 but 50pct were probably some built VFO rubbish. I bet most were sprog boxes, badly tuned into bad aerials with coax radiating and VFO ones at that, mono and a rip off for what they were, simply hard to get old off so pirates got ripped off for them. Most likely most of those had harmonics worse than a QN 8007 BK 1414K chip ! Less the rose tinted glasses.

Demand is clearly low now as normal block pirates are fewer these days it is not a plan to compete with Capital 95.8

It is worth remembering that in the right place with even the most basic well tuned antenna dipole / gpa.. 15W will do 20miles + in all directions mono. And maybe 7 listenable in stereo. Much better than an average London pirate manages with all the band clutter, raids, rig theft etc. Only a few respected die hards carry on with that.

[FMEnjoyer]

On the BH1414K chip.

It looks pretty unbogus to my eye.

What more are people wanting? I have seen more Chinese rig anaylsis than so called UKEuro expert builders who seem to have a lot to say. Where are those spectrum analyzer videos ?

[radionortheast]

needs a 2 volt audio signal to drive, almost unusable.

The volume always seemed fine to me, the earliest one I had the pilot level was to high, there was sound solution that would keep the volume at the same level, it didn’t work with protected wma files though. They won’t interfere sprog if theres a miss match, thermal protection also stops them going into thermal runway, they shut down. People said avoid the stmax, I might of had one at one bit, i’m not sure, better to get newer 8000 ones than the 2015, the 2015 was the only one had a problem with, it went wrong after a year, might of been laying about some were. The 3000 pc boards were the best, indestructible, they had rds too, the 5v regulator would break on them sometimes.

[mikroman]

"requires 2 volt audio signal to drive".
I'm also interested in which series it is. The sensitivity of the MPX input on series 3xxx, 6xxx and 7xxx is adjustable down to 0.3V for 75K deviation. Due to the passive RC network, the only sensitivity problem occurs when trying to use preepmhasis and mono. Also, if you are a frequent customer, there is a good conversation with the company director about some of the repairs that you can do yourself. I have several boards from the 2015+ series that have been driving for several years without a single failure. The only drawback of this series is the deficiency in the band below 100Hz (phase distortion). It is only important that the modules are not in a humid area and, and considering the flow of the fan, if necessary, it should be cleaned time to time.

[shuffy]

PCS cost a fortune to import into UK, there basic add ons that should be included are triple the price they should be, they look to be PLL as you say + courier fees, import duty, VAT and other potentially unknown costs.

I hadn't reaslised that about PCS! I've just costed up a 15W stereo/RDS tx with LCD board though and included delivery to the UK and VAT and it comes to around £150. I think (could be wrong) there's a concession on import duty below something like £140, is that right? Anyway yeah it's a bit pricey. It's not much more than the "oazz" rig from another thread though. Granted it's swings and roundabouts and subjective benefits.

With regard to your comment about surface mount, if you want stereo, RDS and a nice friendly PLL UI without an all-in-one chip, it's the only way to go unless you want a massive board. That said, the BH/Q devices are mostly surface mount, aren't they - and you're going to need a microcontroller to control them and run your UI.

Hard to disagree with anything else you said. It's just about the application for me. I'm not slagging the chips off, for what they are, some are impressive. I'm just not looking at them as components of a broadcast TX (and neither, I think, are the manufacturers).

Obviously if it can be proved that the chip output is within spec I wouldn't try to stop someone using it in a rig, but personally I wouldn't as I wouldn't want the stereo or RDS (I think you're limiting your options). So if all I want is the modulator, I'd rather make a discrete one for not much more than using a chip.

From a rig building point of view, I've thought pretty hard in the past about what you want from an exciter to be as flexible as possible in a broadcast system and my conclusion was, stable, clean output variable from 0.5 - 3W but no bells and whistles. So it's cheap, disposable, and doesn't limit your PA or baseband options. I'm aware that this market is comparatively small these days. It's in yer blood though, innit!

[Albert H]

It's funny that people seem to think that "block-based" broadcasters are a thing of the past. One regular rig-builder I know is getting more work than ever - perhaps many of the "regulars" are retiring from the game.

Constructing reasonably powerful rigs is quite easy these days (assuming you've got all the relevant test gear). A 200 Watt PA can be fully driven with less than a Watt these days, as the gain of some of the FETs available is astonishing. I remember the "bad old days" of RF power transistors with 6 - 7 dB of gain. A 40 Watt output PA could need as much as 7 Watts of drive back then. These days, we've done away with the driver stage, as a flea-power exciter will fully drive those FETs!

PLLs used to be difficult. Getting prescaler ICs that would go fast enough could be expensive, as they were quite rare. The Plessey ECL chips (SP8629 was a favourite) were a game changer. The prescaler would divide by 100, bringing the Band II signal down to CMOS data rates. I used to use the Plessey SL560 (a three-transistor amplifier in an 8-pin DIL package, with the base and emitter of the first transistor on two of the pins, allowing configuration as a Colpitts oscillator) for the Band II oscillator and buffer, driving into a 2N4427 giving about 750mW. The PLL would generate a reference at 1/100th of the output frequency, and this would be compared with the prescaler output to give a steering voltage for the Band II oscillator. For the first time we had rigs that didn't drift at all!

[EFR]

I belive to numbers what my testgear shows, these are numbers what my R&S CRTU-RU did show.

Im out of this discussion, real power at 100Mhz was about 11.2W, Daiwa did show about 15.5W.


https://ibb.co/xJ8v1Dt
https://ibb.co/j8fBZbh
https://ibb.co/86WL7Gg
https://ibb.co/L0Vy1jW
https://ibb.co/54LSSxg
https://ibb.co/7SdCyqq
https://ibb.co/dpWzpdX
https://ibb.co/8Yd0YjY
https://ibb.co/RTXNRDb
https://ibb.co/G2fJzv9
https://ibb.co/bbmg94X
https://ibb.co/cr9dxDR
https://ibb.co/4svvgw2

[EFR]

I think this one says everything.

https://ibb.co/7SdCyqq

[EFR]

Last message went to an space, same text here but shorter.

After cup of coffee and couple cigarettes:
Input power was 5.2A at 13.82VDC measured by my Agilent 34405A (Whopping 70Watts!)
It was powered from an nice inhouse build linear powersupply, 30A at 24/7 so there was some headroom.

PA stability was good, spectrum did stay same feeding diffrent dummyloads from 25ohm to 75ohms.

Real power at carrier was about 11.2W, Daiwa did show around 15.5W with all sprogs.

Build quality and case finnish was nice.

Frequency was allways about 2-7.5kHz down, drifting about 9.2kHz quite fast.

Transmitter was feed to dummyload via inhouse made power coupler with attenuation of about ±5dB with all coaxes and connectors, tested linear from 5Mhz to 750Mhz.

I personally would not to plug this device to an antenna.