Skywave AMPS

[lrz50]

Anybody heard of these amps? There's a Dx-350 And Dx-500. Kind of pricey $650.00 and $950.00. Look at the way the pills are mounted.
/www.ebay.com/itm/SkyWave-DX350-RF-Linear-Amplifier/264224133164?hash=item3d84fc502c:g:fysAAO

/www.ebay.com/itm/SkyWave-DX500-RF-Linear-Amplifier/264183109447?hash=item3d828a5747:g:rfIAAOSwv

 

[Beetle]

And the metering is … ?

 

[Handy Andy]

I smell a...

http://cbradioblog.com/

 

[unit_399]

Construction and soldering looks good. Problem is the cost (way too high) considering it uses MRF454 transistors. At 13.8volts, the "500" certainly isn't representative of the power output (which they don't quote). I'll pass

- 399

 

[999]

He uses plastic boxes for the amp case.

 

[AudioShockwav]

Agree with 399.

73
Jeff

 

[Shadetree Mechanic]

I don't see these as being any better than Texas Star. It seems to me that a plastic box would leak RF everywhere.

 

[Tallman]

Way too damn expensive for what you are getting! Plastic box? Not worth what they are asking.

 

[Tallman]

I smell a...

http://cbradioblog.com/

View attachment 28296

Yep and it don't smell good either.

 

[nomadradio]

Seems to me Brian used a trick in his Skywave boards that was also seen in the "LA" 800 and 900 amplifiers. He feeds the DC power to the RF transistors though a common-mode choke made from ferrite cores straight to the output-transistor collectors, and not into the far end center tap of the ferrite RF-output transformer. It's a trick Helge Granberg shows in his book from 1993. This way only the RF current flows in the output transformer, rather than the RF and DC supply to the collectors, both.

This increases the RF power level that saturates the core of the RF-output transformer. This is how the "LA" boxes would show 200 Watt peaks per each 2879 with only a 14-Volt supply.

Brian's no fool. Has an actual engineering background. His videos do make me scratch my head sometimes, though.

His prices suggest that he has a day job and doesn't really need the money.

Maybe.

73

 

[Eldorado828]

Yeah he's been building them for a few years now that I can remember. I see the prices have jumped significantly from the last time I saw them. I was curious a few years back and asked him a few questions about them and I will always remember he always started his replies with "these amplifiers are only for the serious operator" but he seemed to be a good fellow. Needless to say I guess I wasn't a serious operator so I didn't get one haha

 

[Handy Andy]

I warned all of you about the issue of Trolling - so let it be written, so let it be done...

I'll let those that judge, judge, and let those that are Curious, be Shown, and to the rest of us, we don't have to float about on eBay to inflate egos for hits, nor Followers of Facebook to get flagged for Flogging, nor NewsGroups that got spammed - let us not to be taken - too Seriously...

The DX350

The DX500

Let your Research - Help you to decide...

 

[999]

I warned all of you about the issue of Trolling - so let it be written, so let it be done...

I'll let those that judge, judge, and let those that are Curious, be Shown, and to the rest of us, we don't have to float about on eBay to inflate egos for hits, nor Followers of Facebook to get flagged for Flogging, nor NewsGroups that got spammed - let us not to be taken - too Seriously...

The DX350
View attachment 28313

The DX500
View attachment 28314

Let your Research - Help you to decide...

That looks like 14Ga wire on that "DX500" to me. Just a TAD small, dontcha think?

 

[lrz50]

I found all the specs on these amps.http://www.telstar-electronics.com/

 

[Eldorado828]

There's been a 250 of these listed on ebay for a few weeks now and doesn't seem to get much interest. I see the seller is down to 140 and still no sale. I remember this thread and just thought I'd make a mention.