Years ago I remember buying some acid-based flux that was used to solder aluminum. Maybe this is also an option but I am not sure if it will work soldering copper.

HA5RXZ

Don't do it.

1) Any antennas and your mast will get covered in soot and grime. This may affect their operation.

2) The vibration and wind load will eventually loosen mortar and brickwork.

3) You now have a lightning conductor fixed to your chimney, this may not be a good idea.

HA5RXZ

-The HBX is not rated for climbing; that implies you must preassemble your antenna(s) onto it prior to raising the tower;

No it doesn't. It means that the tower cannot hold the weight of a human adult hanging off of it. You could always send up a child but I think that might be illegal in the USA.

-The HBX is also not rated for tilting it up from horizontal to vertical once an antenna load is installed above the tower.

OK, this implies that the tower can only handle its own weight when moving from horizontal to vertical.

So, raise your tower by either using a hire crane or (if you are feeling brave) 'walk' the tower up to a vertical position. You then use either a crane or a cherry picker to place the antenna(s) on the tower.

Remember, gravity sucks.


HA5RXZ

Unless you are building your mast out of copper pipe then straps made from copper would be a very bad idea. Dissimilar metals will corrode when there is moisture around.

I don't see the need to strap but if you really want to then use the same metal as your mast section.

HA5RXZ

1) Plywood door picked up from a hardware store for a song as it has a scratch on one side. The scratched side goes underneath and nobody will ever know.

2) Two two-drawer filing cabinets from a shop selling reconditioned office furniture.

Make sure you put some screws through the top of the filing cabinet and into the frame of the door. If you don't your desk will tip over the first time you put something on the back (been there, done that).

Total cost 20,000 Forint or about a hundred bucks.

HA5RXZ

I am not sure how this is spelt but I would use a Gin pole. With your tower horizontal the pole is vertical (and attached at MULTIPLE points to your tower.

If you then attach the top of the pole to a convenient car using a rope or chain this can aid in the lifting operation.

HA5RXZ

OK, thanks for that. Apart from the fact that most of the site readers are based in the USA I always remembered the figure for the speed of light as 'one nanosecond a foot'. I therefore made the post in imperial measurements although metric is easier for both of us.

My guess at 5.5 feet of cable was pretty close though, 1.66 metres in feet is 5.446 feet or 5 foot 5.35 inches.

HA5RXZ

I want to create a circuit that will provide two sine waves at 45 MHz with one output 90 degrees out of phase from the other.

1 / 45,000,000 = 22 nanoseconds

22 nanoseconds / 4 = 5.5 nanoseconds

So I need to delay the second signal by 5.5 nanoseconds to provide a 90 degree offset. I could do this using about 5.5 feet of coax cable but does the velocity factor of the cable increase or decrease the length in this application?

HA5RXZ

Thank You!!

In nearly thirty years of ham radio that is the clearest explanation of SWR theory I have ever seen, and all you used was ohms law.

If you are ever in Budapest I'll buy you a beer.

HA5RXZ

This is one of the few occasions when Google falls down. Keying in any of the four ICs above gives hundreds of sites offering to sell me the chip(s) but no application data. The closest I'm come so far is the NTE site which gives me a pinout and a little bit of information but it's only two sheets.

The chip was originally manufactured by NEC but they stopped production 12 years ago and have no data. It was used in a number of cheap radio cassette units including the Sanyo unit I have to fix. I suspect that this repair could take a while!

HA5RXZ

Looking for a datasheet for the NEC UPC1018C AM/FM receiver chip. Tried Google and lots of folk want to sell me large quantities but none have the data.

Any (working) urls for the pdf would be appreciated

Tnx

HA5RXZ

This is the sort of reason why I don't subscribe. The site was down for two days with no advance warning and no explanation once it reappeared again. Add to that the fact that it's as slow as treacle once the USA wakes up and you can see why you don't deserve my money.

Yes, I will support the site by answering queries from fellow hams and I may contribute an article once in a while, but if you want the cash improve your service.

HA5RXZ

No, the K2 is not an option here for the following reasons:

1) No AM receive.

2) No general coverage, ham bands only.

As I said at the start of this thread the rig will be used for both ham work and SWL work on the broadcast bands, the K2 is therefore a none-starter.

HA5RXZ

If you post the specifications of this part (input volts, output volts, output current) I will see what I can find for you.

HA5RXZ

See http://mrtmag.com/mag/radio_tower_climbingsafety_rescue/index.html for some safety advice. 160 feet is a long way to fall.

HA5RXZ