thewoodstarr wrote: ↑Wed Feb 20, 2019 1:34 am

teckniqs wrote: ↑Fri Jan 18, 2019 10:32 am ^^ With equipment like that, it's no surprise to see articles like this....

https://www.gazette-news.co.uk/news/551 ... air-alert/

Fire it up bro! No LRF on it, it will be alright! It's going to be <100 Watt.

Fire what up.... bro?? What on earth you been smoking that you shouldn't have tonight then?

mixfm wrote: ↑Sun Jan 27, 2019 11:58 am heres a 50 watt alan rig we had knocking around, the rig we used to install last result. lol memories... built in a disco light...

This rig used to push 20 watts ... The best part about it tho .. I used to have a sound level LED bar on the front .. But used to turn the lift room in to a disco ..

R.

piradio wrote: ↑Sun Feb 24, 2019 8:51 pm

mixfm wrote: ↑Sun Jan 27, 2019 11:58 am heres a 50 watt alan rig we had knocking around, the rig we used to install last result. lol memories... built in a disco light...

This rig used to push 20 watts ... The best part about it tho .. I used to have a sound level LED bar on the front .. But used to turn the lift room in to a disco ..

R.

Did it also push half that power on 118MHz giving pilots some entertainment on their radios?

I have definitely seen rigs like that in the 90's VFO, copper clad, though to be fair I only ever had 2 rigs and really just messed about with them locally.

It's old but it still works 10w @12v

You want to carefully unsolder those "tropical fish" caps and sell 'em on Ebay for >£5 each! Replace them with cheap ceramics.

Albert H wrote: ↑Wed Apr 17, 2019 11:35 pm You want to carefully unsolder those "tropical fish" caps and sell 'em on Ebay for >£5 each! Replace them with cheap ceramics.

Wow I haven't seen anything like that in years, it pre date`s me by many years. It maybe a band 1 TX, but looking at it, it seems to have doubling coils? I would not try and use that, however there are people out there that buy old stuff like that, and they will pay a good penny for it. Its History! Please don`t scrap it.

Looks to me like an old Bowman VCO (who's stopped building now)

....And an old PYE p.m.r radio or taxi radio power amplifier.

Anyone with half a braincell of building experience can see it's band 2 and not band 1 just by the number of turns in the coils.

For the benefit of thewoodstarr this is a band 1 TX

What a state, don't try and use that! Its an old Gel/Keith PLL lumped together with a load of 2n6369a`s into MRF237. That has got to be the worst I have ever seen. That's not a band one, its just a fuckin mess. lol

Is that your best gear. You lot make me chuckle, no idear. You lot carry on.

teckniqs wrote: ↑Fri Apr 19, 2019 8:32 am Looks to me like an old Bowman VCO (who's stopped building now)

....And an old PYE p.m.r radio or taxi radio power amplifier.

Anyone with half a braincell of building experience can see it's band 2 and not band 1 just by the number of turns in the coils.

Persons who think they can build, should get out there and build, once said person has done so, he or she can post comments on this site, if not, shut up, you complete fraggle.

How many stickers can you spot inside a woody rig? The winner gets £200 of woody made in the UK notes and some cider

Bloody amateurs! Here's two sides of an old link repeater:
Input in Band V, output in higher end of Band 1. Used for about 8 years in the western USA. The studio output was microwave across the street to a building with a better view of the first hilltop....

At the top of the first big hill, there was a waterproof diecast box with the link repeater in it, There was a TV aerial pointing back towards the town, and a Band 1 "H" pointing towards the output site, which was five miles away. The link repeater was installed up a telegraph pole!

THE GOVERNOR wrote: ↑Fri Apr 19, 2019 6:24 pm How many stickers can you spot inside a woody rig?
Screenshot_20190417-141742_eBay.jpg

The winner gets £200 of woody made in the UK notes and some cider 20190419_181109.jpg

Thanks for the add, muppet!

Albert H wrote: ↑Sat Apr 20, 2019 3:52 am Bloody amateurs! Here's two sides of an old link repeater:

Front.jpg

rear.jpg

Input in Band V, output in higher end of Band 1. Used for about 8 years in the western USA. The studio output was microwave across the street to a building with a better view of the first hilltop....

At the top of the first big hill, there was a waterproof diecast box with the link repeater in it, There was a TV aerial pointing back towards the town, and a Band 1 "H" pointing towards the output site, which was five miles away. The link repeater was installed up a telegraph pole!

That is nice, nothing wrong with that.

THE GOVERNOR wrote: ↑Fri Apr 19, 2019 6:24 pm How many stickers can you spot inside a woody rig?
Screenshot_20190417-141742_eBay.jpg

The winner gets £200 of woody made in the UK notes and some cider 20190419_181109.jpg

Is that the best you can do! Its a legal requirement to label AC mains in all Electronic equipment.
Thanks for the Add, do you know what? I never have liked Strongbow! lol
Fucking Muppet! Go and do some more Photoshopping!

THE GOVERNOR wrote: ↑Wed Apr 17, 2019 3:43 pm It's old but it still works 10w @12v
20190417_153843.jpg

The exciter on this looks to be identical to one i had given in the early 90's but it was set up as a uhf link tx, the oscillator was on 50Mhz with tripler to 150Mhz out fed to a seperate small copper clad board with a varactor tripler and a low power uhf amp.

Back in the 80s and 90s, there were quite a few PCB exciter designs around. Roger H (now at Broadcast Warehouse) had a neat little PCB that gave about ½ Watt and was quite stable and clean. He later tacked a PLL PCB beneath them to ensure their frequency stability.

My PCB design in the 80s was a double-sided board that could be used on any band from Band I to Band V just by changing the coils and a few capacitors. These were designed to have a CMOS PLL, and the VCO would work between 40 and 70 MHz. The Band I version was "at frequency", the Band II version used a doubler stage, the Band III version used two cascaded doublers, and the Band IV and V versions used Varactor multipliers and grounded base driver and output stages. All of them delivered between 750mW and 1.2W,and all used the same PLL with diode programming to set the frequency. They were designed to fit into a standard tinplate box.

Dawson had a PCB that Kenny Myers designed. This was a doubler design, and used a four-chip CMOS PLL. If built correctly, with the right components, it was actually pretty good for its day.

There were many others around. Bonex sold a kit for a "1 Watt" VFO exciter that used a neat row of Toko S18 coils, but wasn't particularly frequency stable, and could be tuned up to deliver lots of different frequencies at the same time!

There was a big, square PCB that the Invicta rigs used. It had the most complicated coil assembly that I ever saw in a rig - several coils on the same former, with some of them overwound with secondaries. This board went beneath the chassis of their standard rigs, and the top of the chassis had the mains transformer, smoothing capacitors and the amplifier stage valves. Their final was usually a QQE06/40 which could be critically tuned to give as much as 100W when the anode voltage was cranked up a bit. Their rigs always drifted because of thermal problems, but Bob Tomalski (RIP) and the rest of them couldn't accept that their design wasn't ideal!

These days, surface-mounted components seem to be the way to go - particularly at higher frequencies. "Leadless" components get rid of the problems of lead length, but introduce problems of their own.

A recent PCB design I saw (from a well-known rig supplier) had a problem with going out of lock after it had run perfectly for an hour or two. I put one of these on the bench and tested it, and discovered that the VCO Control (Tuning) Voltage would slowly drift downwards as the PCB warmed up. The final stage was a pair of BFG135s running in parallel to give about 1.5 Watts from the board - ideal drive for their following amplifier stages. Unfortunately, the output stage heat would warm the oscillator enough through the groundplane so that the Control Voltage would head towards ground, and when the loop filter op-amp couldn't get any lower in output voltage, the loop would go out of lock, shutting down the rig. It would cool off, and re-start, and then go off again!

Silly design errors like that have always helped me in my design work - I learn from them, and don't make the same errors myself!

where i can find a doubler and a tripler i wanna try ?