guess who got smoked up last night?

[KE1GF]

Hehe, there was a snap and a flash and the overload tripped. I reset the latch and keyed up
telling the gang on 75 that my transmitter was on fire... I just let it burn

The good old 'GF 20 pill thrill must be jelous of the new driver technology that I've developed
I think she's asking for an refit and an overhaul.

[David, K3TUE]

[...] The good old 'GF 20 pill thrill must be jelous of the new driver technology that I've developed [...]

What new driver technology, prey tell?

[W2PFY]

Boy, They don't build those radios like they they did in the old days

[KE1GF]

[...] The good old 'GF 20 pill thrill must be jelous of the new driver technology that I've developed [...]

What new driver technology, prey tell?

Dave, I posted it in the online handbook, under transmitters. I'm working on the prototype,
it's designed from tried and tested tech that I've done here in the lab. It can be used as a power
sine wave driver for a big class-E final or a standalone modulatable final. I presented it with shunt
caps and an output network so that it could be connected to a 50 ohm antenna. Fed with a
QIX modulator and used on 75m. I put in an order from cws/bytemark and digikey for the parts
to built the first one, it won't be pretty (dremel and a copper clad board) I have hopes that express
pcb can make me a board once I get done with the first one, and then I'll give away the artwork
as part of the project.

I'm really an R&D scientist, not an engineer.

[KE1GF]

I've found the cause of the failure, one of the series LEDs in the sequencer/control is intermittant, this has happend before. Last time it happened I was lucky and the LED in the final sequence stage went and the main PS chattered, so all the required drive stages were okay fine and no damage occured. This time it was the Totem-Pole driver stage control, which drives the single ended class-E amp that drives the final PA. With my DC coupled Totem-Pole, if anything goes wrong, the sink FET latches the gates of the Class-E driver FETs to ground. So no damage occured to the final driver stage.

I'm going to re-design the relay controls for the sequencer using mosfets to switch the relays and have the LEDs in parallel instead of in series with the relays. I made a boo-boo when I put the LEDs in series with the relays, they're not designed to handle the current. I made a stupid mistake. live and learn

[Glenn NY4NC]

Wow Bill... looks like there was a frat party inside your transmitter  ....

You shouldn't have posted that here... The anti-Class-E guys are gonna bust your hump fer sure 

[KE1GF]

Wow Bill... looks like there was a frat party inside your transmitter  ....

You shouldn't have posted that here... The anti-Class-E guys are gonna bust your hump fer sure 

Glenn, the who are the anti-class-E guys?

I've already received my initiations, at least I beleve so... All transmitters blow up, just some go up with a bigger bang and price tag than others. It's not really a technical thing, just intresting and funny to see a transmitter that has been running smooth for a few years now finally crap out. 

Replacing $10 worth of FETs in a RF-Deck and adding 4 P-Chan FETS to a sequencer isn't so bad.

[Glenn NY4NC]

Just making a yoke...

I understand Bill, you paid your dues and sang the blues no doubt.... I got a kick out of your comment that you just let it burn 

[Glenn, the who are the anti-class-E guys?

Do I dare say, another guy named Bill? 

[W1IA]

I've found the cause of the failure, one of the series LEDs in the sequencer/control is intermittant, this has happend before. Last time it happened I was lucky and the LED in the final sequence stage went and the main PS chattered, so all the required drive stages were okay fine and no damage occured. This time it was the Totem-Pole driver stage control, which drives the single ended class-E amp that drives the final PA. With my DC coupled Totem-Pole, if anything goes wrong, the sink FET latches the gates of the Class-E driver FETs to ground. So no damage occured to the final driver stage.

I'm going to re-design the relay controls for the sequencer using mosfets to switch the relays and have the LEDs in parallel instead of in series with the relays. I made a boo-boo when I put the LEDs in series with the relays, they're not designed to handle the current. I made a stupid mistake. live and learn

Bummer Bill....well it was bound to happen. I modified the sequencer after looking at those led's in series with the relay coils and ran some in parrallel instead....you make me happy I did. Oh well.
Strap in the new parts and we will see you on the air!

Brent

[KE1GF]

Yep that's pretty much the game plan dude. I'm just getting my strength back from sinusitis and bronchitis with some pneumonia. So I work for a few hours and rest for a few. I have a dry hacking cough, I worked all the fluid up... I'm wearing the nicotine patch and cut way back on the butts. I've had a nice taste of what it's like not being able to breathe, not fun!

I'm waiting for digikey, gonna build the proto for my new driver

[WA1GFZ]

LEDS in series with relay coils wow you must be using some large leds......or they are begging for mercey.

Every rig blows up just some guys can't admit it. Kind of fun as long as the house doesn't burn down.

BUTTS KILL, you are a smart guy Bill...................

[KE1GF]

LEDS in series with relay coils wow you must be using some large leds......or they are begging for mercey.

Every rig blows up just some guys can't admit it. Kind of fun as long as the house doesn't burn down.

BUTTS KILL, you are a smart guy Bill...................

Yeah frank I don't know where my head was at when I built the thing... And when It broke the first time
I just stuck a new LED in there and completely forgot about it... Must of been something to do with the old
man's last few months on earth.

[K1JJ]

Glad you got a handle on the problem so fast, Bill.

BTW, my own class E 20 piller popped one of its four RF power modules last week. I was cranking up the power for a new dipole and suddenly one of the current meters went negative.

I got yellowfied and decided to take it off line for awhile and stick it in the cellar. I'm now designing up a new 4-1000A modulated by a pair...  Either that, or a set of quad 813's modulated by a quad set.  Just gotta find a decent 1KW mod transformer. Sold my big iron 5 years ago. Got all the other parts and motivation.

I do miss the tube plate modulated stuff. [I must admit]

The E rig will resurface later on once I get the big tube rig running.

So, just wanted to let ya know you're not alone, OM... 

T

[KE1GF]

Glad you got a handle on the problem so fast, Bill.

BTW, my own class E 20 piller popped one of its four RF power modules last week. I was cranking up the power for a new dipole and suddenly one of the current meters went negative.

I got yellowfied and decided to take it off line for awhile and stick it in the cellar. I'm now designing up a new 4-1000A modulated by a pair...  Either that, or a set of quad 813's modulated by a quad set.  Just gotta find a decent 1KW mod transformer. Sold my big iron 5 years ago. Got all the other parts and motivation.

I do miss the tube plate modulated stuff. [I must admit]

The E rig will resurface later on once I get the big tube rig running.

So, just wanted to let ya know you're not alone, OM... 

T

Sounds cool OM.

I have a nack for building things out of commodity hardware.

There is a part of me that would like to do lots of "larger than life" things, yet there is another part that says be practial.

I really truely believe that I'm the last of a dying breed, I hope with my totally radical designs that I spark somebody's interest. My hope is that we get some bold young blood on AM, to carry on the true spirit.

[W2JBL]

  i was on that night with Bill and a bunch of case hardened tube guys. when he had the failure nobody really busted his chops. and to his credit- he cooly exclaimed "my transmitter is on fire", in fact he actually came back a few more times until it farted out. S*&T happens to all of us. anybody who can continue to transmit after saying his transmitter is on fire is a true AM'er to the max. hope you get it sorted out, Bill.

[WA1GFZ]

Bill,
All of us would like to see you create new interest since you are the youngest guy in the gang. Once there was a pile of older guys we looked up to or laughed at. Soon you will be laughing at all of us.
I prefer the radical approach. The modify my ranger years were quite a bore to me.

[KE1GF]

I made the updates to the sequencer, didn't use p-chans though, I already was using bipolars (2n3906s), so just put the leds with a current limit resistor in parallel.

Along with replacing the blown FETs in the final and cleaning off the smoke residue with some alcohol swabs, I updated the RF bypass caps to higher quality paralleled values...

I gave it a good beating on the dummy load and then worked Tim 'HLR and Gary 'OXT, should be good until the next crap out

[WA1GFZ]

I'm very interested in sequencers and fail safe systems.
K.I.S.S. is key

[KE1GF]

Yeah frank, maybe my next rig will have a bastardized smoke detector in it... haha 

Actually, it's not a bad idea, put a halon bottle with a solenoid inside the cabinet, maybe bill 'IFR can contribute.

[WA1GFZ]

Bill,
I sent a good Broadband Trandformer app note to your WPI email address. I wonder if it is still good?

[KE1GF]

Yes, Frank, it's still good. I'm back at school working on my MQP, 9 credits to go for the sheep skin.
I'll have an alumnus address there in the future.