What transmitter recommend?

Sietedj · Post by **Sietedj** » Fri Apr 08, 2016 8:18 pm

Hi, I had planned to buy the Dutch FM DRFS06 but no stock.
I saw these two and wanted to know your opinion:
http://www.amateurradioshop.nl/products ... 5&cPath=55
This is a kit but can send mounted, for 90 €.
http://www.hf-electronics.nl/Webwinkel- ... 6watt.html
This not know if it is a kit or already assembled.
Thank you!!!

Maximus · Post by **Maximus** » Fri Apr 08, 2016 10:34 pm

I'd go with the second tx from hf electronics.
It's their latest redesign of a well known transmitter that works.

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teckniqs · Post by **teckniqs** » Fri Apr 08, 2016 10:53 pm

Will the RD15 go straight in the 6w version in the second link or does it need a little more drive? Think I vaguely remember someone saying you can simply swap over the RDVV TX's 6w device for the 15w??

Sietedj · Post by **Sietedj** » Fri Apr 08, 2016 11:03 pm

Hi, thanks for the comments. I have enough 6W then want to make an amplifier, but later. Although 15W would be better to start

Albert H · Post by **Albert H** » Sat Apr 09, 2016 12:28 am

Techniqs - the RD15 needs a bit more drive than the RD06, but the RD15 is capable of almost 25Watts (without bursting) if you get the matches right and the bias spot on!

RF-Head · Post by **RF-Head** » Sat Apr 09, 2016 7:24 am

DTRFS06 is a good transmitter module
HF-Electronics is more simple to built (it's mine)

Amateurradio thing having problems with sproging and going out of lock because of the smal design and the RD15 nex to the oscillator
here in NL not used by pirates

RF-Head · Post by **RF-Head** » Sat Apr 09, 2016 7:26 am

The 6W module will work with a RD15 but maybe then using a little fan over the heatsink

MiXiN · Post by **MiXiN** » Sat Apr 09, 2016 11:47 am

RF-Head,

What happened to that driver board you repeatedly told me I can buy off you but haven't?

I've been waiting that long and asked for it on that many occasions I've lost count!

Sietedj · Post by **Sietedj** » Sat Apr 09, 2016 4:15 pm

Then both you recommend the HF Electronics. I understand that you can mount a RD15? It is difficult to adjust? I have no measuring equipment so I prefer one that is already assembled and adjusted.

RF-Head · Post by **RF-Head** » Sat Apr 09, 2016 8:19 pm

Better go for this one then
http://www.hf-electronics.nl/Webwinkel- ... odule.html
Will be giving 30 Watts of clean power and mounted on heatsink and SWR protection

Sietedj · Post by **Sietedj** » Sat Apr 09, 2016 11:32 pm

RF-Head wrote:Better go for this one then
http://www.hf-electronics.nl/Webwinkel- ... odule.html
Will be giving 30 Watts of clean power and mounted on heatsink and SWR protection

You know if you carry LCD screen? They do not give much information about it.

Sietedj · Post by **Sietedj** » Sun Apr 10, 2016 12:05 am

This is similar and cheaper, which is the original and which the copy?
http://www.ebay.com/itm/DC-12V-Digital- ... 1253037672

Undercover Neckz · Post by **Undercover Neckz** » Sun Apr 10, 2016 2:00 am

MiXiN wrote:RF-Head,

What happened to that driver board you repeatedly told me I can buy off you but haven't?

I've been waiting that long and asked for it on that many occasions I've lost count!

Haha you need to chill out a bit mate or you'll never get one.

RF-Head · Post by **RF-Head** » Sun Apr 10, 2016 8:54 am

The chinese ebay one is not the same!
It use a MP3 fm transmitter chip to generate stereo and RF signal
This will give lots of spurs in the FM dial and even higher
The outputstage of the chinese one was good and used in the dutch version
The oscillator is using a mosfet and has 4 varicap diodes for modulation and pll
There is no LCD display on this module because most of the time there used by stations that using 1 freq
Frequency can be changed by 2 pushbuttons

Sietedj · Post by **Sietedj** » Sun Apr 10, 2016 9:30 am

RF-Head wrote:The chinese ebay one is not the same!
It use a MP3 fm transmitter chip to generate stereo and RF signal
This will give lots of spurs in the FM dial and even higher
The outputstage of the chinese one was good and used in the dutch version
The oscillator is using a mosfet and has 4 varicap diodes for modulation and pll
There is no LCD display on this module because most of the time there used by stations that using 1 freq
Frequency can be changed by 2 pushbuttons

Ok I understand. Then I will consider this transmitter 30W
Thank you!!!

Albert H · Post by **Albert H** » Sun Apr 10, 2016 11:28 pm

Sietedj wrote:This is similar and cheaper, which is the original and which the copy?
http://www.ebay.com/itm/DC-12V-Digital- ... 1253037672

This Chinese one is pretty poor. They use a single chip as the oscillator, stereo coder and PLL. This chip was designed for use in those little "car transmitter" efforts, used to send the output of your iPod to your car radio. The spurs and adjacent channel noise that these chips produce don't matter when you're radiating 5mW inside a metal box (a car).

However, if you amplify the mess that these chips produce, you're certain to cause interference. They have bothered with a low pass filter, so there shouldn't be much at 200MHz, but if you were to set it to (say) 107.5MHz, there would be substantial crap getting into the air-band. This is certain to get you a very rapid "unfriendly visit"! Also, if you fired this up anywhere else in the band, you'll cause loads of local interference to other stations - again ensuring a rapid visit.

Buy the Dutch one. They've been making good gear for years, and some of the innovations that I've included in some of my gear were originated over there! I like their use of the 5511 PLL IC and a proper loop filter (giving low phase noise, clean carrier and low adjacent noise), and their use of the coaxial resonator for their VCO is pretty sensible (and something I've done for the last 25 years!). They've used the same FET as the Chinese board - a sensible choice for use at <15V - and they've rated it (nominally) at 30 Watts. I've had about 50 Watts out of this device, in a very similar circuit, but it requires a lot of heatsink, and any load error will cause its instant destruction!

The Dutch board at €150 is sensibly priced.

Sietedj · Post by **Sietedj** » Mon Apr 11, 2016 3:00 pm

Thanks Albert H, as saving a little money I buy this Dutch.
Thanks for the imformacion !!

teckniqs · Post by **teckniqs** » Mon Apr 11, 2016 4:08 pm

Good choice been using the dutch stuff for past 12 years and never let me down.

Sietedj · Post by **Sietedj** » Fri Jul 15, 2016 9:54 pm

RF-Head wrote:Better go for this one then
http://www.hf-electronics.nl/Webwinkel- ... odule.html
Will be giving 30 Watts of clean power and mounted on heatsink and SWR protection

Hello, last week bought this transmitter but do not respond to emails, I want to know how long it takes to ship orders but no one answers. Anyone know how long it takes to send something? It does not seem right that no one respond to queries.
Thanks and regards!!

RF-Head · Post by **RF-Head** » Sat Jul 16, 2016 8:46 am

I'm on vacation at the moment and back this weekend
I have the module in stock and only need to change the things you ask.
And can post it begin next week
I will reply you mail when i'm back
(was away only a few days)
The guys in the shop doesnt reply on any technical mails when i'm away