Opinions on another driver?

[teckniqs]

http://www.ebay.co.uk/itm/FM-BROADCAST- ... Sw~bFWMRJ1

Anyone ever seen these before? Looks very cheap for only £23.00

[pjeva]

Looks like combination of rdvv 300mW and LM7001 pll. It can be remake of some RVR designs... I am realy not sure what makes this nominal 500mW. Output device looks like 50 - 100mW max...


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[Analyser]

I was somewhat interested in buying one to test but it's sold already. There have been a few on sale before but they seem to go pretty quickly. Everything that guy sells is ridiculously cheap, you have to wonder how he makes any money at all after the Ebay fees and postage he has to pay, not withstanding the time he needs to build them.

[teckniqs]

Looks like combination of rdvv 300mW and LM7001 pll. It can be remake of some RVR designs... I am realy not sure what makes this nominal 500mW. Output device looks like 50 - 100mW max...


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The output device looks like the 2sc2053 which I've seen in a lot of old PMR and ham radio gear and good for around 500mW. Being only £23.00 I thought I'd quickly snap it up before anyone else did, I will check it and post the results up for all to see when it's here....

[teckniqs]

The 2sc2053 is only rated at 150mW but will do 500mW, the 2sc2538 which is similar and rated at 500mW will do 1w. And what's really great about them is they're small and don't require a heatsink.

[MiXiN]

Shortly after this one, the seller listed another for £15 but used. That sold sharpish, too.

He's now also listed a 1W RDVV PLL for £20 odd quid as well.

[teckniqs]

He's now also listed a 1W RDVV PLL for £20 odd quid as well.

Thanks for the heads-up, he's now just sold it. I'll be keeping my eyes and ears out with this guy from now on....

[MiXiN]

He's now also listed a 1W RDVV PLL for £20 odd quid as well.

Thanks for the heads-up, he's now just sold it. I'll be keeping my eyes and ears out with this guy from now on....

No worries on the heads up.

They're great deals, that's for sure, but as Analyser said - how is this seller even making any profit?

Please tell us how you get on with both of your buys as I might just buy one of them some day.

[teckniqs]

I sure will, I also bought one of these babies to go with the first PLL. Apparently it's anything from 10-1500mW drive for full output. And for £10 you can't go wrong when the required output device is only £2 on the same website.

http://www.ebay.com/itm/fm-transmitter- ... SwNSxVEDEo

I immidiately thought that too, maybe thats the going rate in Turkey??

[pjeva]

I sure will, I also bought one of these babies to go with the first PLL. Apparently it's anything from 10-1500mW drive for full output. And for £10 you can't go wrong when the required output device is only £2 on the same website.

http://www.ebay.com/itm/fm-transmitter- ... SwNSxVEDEo

I immidiately thought that too, maybe thats the going rate in Turkey??

Input device here is BFR91 and then 2xBFR96 in parallel. If you put 1500mW into this, i'm sure input will burn out...


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[teckniqs]

That's exactly what I thought but the seller insists that it's anything up to 1.5w drive and I'm sure he doesn't want to receive bad feedback for giving buyers false information.
I'll be testing it when it arrives to find out...

[pjeva]

Please provide us results here...


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[teckniqs]

I shall do just that!

[MiXiN]

I sure will, I also bought one of these babies to go with the first PLL. Apparently it's anything from 10-1500mW drive for full output. And for £10 you can't go wrong when the required output device is only £2 on the same website.

http://www.ebay.com/itm/fm-transmitter- ... SwNSxVEDEo

I immidiately thought that too, maybe thats the going rate in Turkey??

I also just bought one of these little amp's and will post an image when it turns up.

I'm thinking there must be some sort of attenuator, perhaps some RF in pad that we can't see if it allows upto 1.5W?

Anyone know of any sources for legit Mitsubishi RD15HFV1 by the way?

[Shedbuilt]

For an amp with just the final (RD15HVF1), you'd need an attenuator to feed it with 1.5W. This has two, fairly high gain stages, before the final, so you'd need to attenuate by more than the combined gain of the two stages; you'd be dissipating almost all of the 1.5W in the attenuator.
It's possible there are details to build it without the lower level amp stages I guess....

[RF-Head]

This amp needs about 0dbm on the input and nothing more
It's a part of my old 15W driverboard
I have also bought one from him and tested and found many problems with it
It's made on single side pcb and was giving spurs from almost 0-1000MHz
He told me to drive the input to a max of 1.5W ?????
There is also a youtube movie from this guy putting his finger on the input and get full power on the output (with a lamp)

[Analyser]

+100

Last few posts are quite right, putting 1.5w into this amp will either burn the input or massively overload it causing spurs all over the place (there's no input attenuator as far as I can see). Also, using a single sided PCB at this power level is asking for trouble.
This circuit is really designed to amplify one of those in-car TXs that output a milliwat or so.
If you want something a lot better which is suitable for broadcast use there are modules available from the UK and Holland which are a lot better and only a few pounds more (you really get what you pay for).

[s2000]

Enigma has a 15 watt board out now..

http://www.enigma-shop.com/index.php?op ... ifier-fm15

[shorty]

This looks to be the layout for the amplifier from turkey

[RF-Head]

yes correct