Other SOTA sites: SOTAwatch | SOTA Home | Database | Video | Photos | Shop | Mapping | FAQs | Facebook | Contact SOTA

45W Linear amp - £12!


#1

Yes, a mere £12 (which includes delivery from China) for a 40dB linear amp kit.
I’m sure the linearity and harmonic supression will meet the conditions of your licence.
Seems ideal to match with the Pixie transceiver :smile:

Don’t all rush at once.

73


#2

That amp is 40 dB because it allows an input of 1-5 mW. The Pixie makes about 1 W, so that would severely overdrive it.

That Chinese amp is 45 W out, but it obviously has no output filters. That might be acceptable in the UK, but it won’t meet the regs in the USA.

If you want a legal amp at that power level, the HARDROCK-50 is a high-quality kit.

https://www.hobbypcb.com/index.php?option=com_virtuemart&view=productdetails&virtuemart_product_id=94&Itemid=402

wunder


#3

I’m not actually suggesting anyone buys one :smile:

Maybe I should have had a tongue in check smiley :-?

Pete


#4

Always use low pass filtering on any solid state amplifier design regardless. No PTT switching circuitry
either which would have been useful for them to include.

There isn’t £12 worth of parts in that kit, everyone wants a PCB nowadays, whats wrong with the scalpel and a bit of elbow grease. This is a fantastic design by W6JL, worth considering if you need a few more dB…

Jonathan


#5

If I read the chart in the advert correctly, the amp needs up to 150V DC to operate at full output on 40m (for example)!

As others have said, no LPF, no PTT/RF-Vox switching but also no heatsink (and this will need one!) and the advert states it’s having to use one recyled transistor as it’s no longer made. By the way this kit uses SMDs. This sounds like someone is clearing stock.

It’s a shame as Ramsey Kits have announced they are closing down (not their instruments section, just the kits division), it would have been nice to have an alternative source for HF amplifier kits. They have some so called “bargain” sell-offs on Amazon & eBAY but I don’t see any bargains - the HF amps appear to be the same price I pais a few years ago.

Ed.