Archive for April 2007

Home Run

April 15, 2007

homerun1.jpgHome Run roses. Found them at Sam’s. Nice, large, flowering plant in a 5 gallon container for 12 dollars. Non-stop flowers, no pruning, thrives in any soil.

Got two of them one for the front garden and one for the side garden. Funny looking petals for a rose. They look more like a large petunia, but they are deep red, have thorns, and smell like roses.

We saw a nice crop of these doing very well in the median on a neighborhood boulevard. They grow to about three feet tall and three feet across.

I figure they will look good against a backdrop of dusty miller around the periphery. Sure hope they are fast growing.

QRP

April 14, 2007

Some people swear by it. I am more inclined to swear at it. QRP is not an option I can consider when I have equipment that is QRO.

Going QRP now would be like trading in my SUV for a moped. I am just not the kind of person that thinks that would be sensible.

I was QRP when I first started in ham radio. I had a 6V6 crystal oscillator for a transmitter, a 6SN7 regen for a receiver, and a long wire antenna that evidently was not long enough because it was difficult to make contacts outside the confines of my town.

All that changed when I got some real equipment and a decent antenna. It never occurred to me to investigate my previous rig to see if it was the transmitter, receiver, or antenna that was the problem. I was having too much fun the with real stuff.

It is not that I think QRP is a bad thing. It is just that I have bad memories about it.

Would I try it again? Probably not. When I first started, QRP was the only thing I could afford. Today QRP is no longer affordable. I think I had all of 50 dollars in my first station. That included antenna, receiver, transmitter, and all the accessories I needed to make them work. Today a basic QRP station is going to run at least 100 dollars. Not that such a price is unaffordable but for 100 dollars I can buy a used QRO rig.

Today QRP just does not make sense to me. Going back to the automobile analogy, QRP is like paying an SUV price for a moped.
Now why would anyone want to do that?

Storms

April 14, 2007

storm.jpgIt is official now. Spring is here. Even though it is unseasonably cool the arrival of storms from the west signal the arrival of spring.

Last night we had some excitement lasting almost two hours. We have been here, in the same place, since 1979 and it has always been the same drill.

Cold fronts come in from the north and west, make their way across Texas, and sometimes bring rain to our area.

Last night a supper dupper weather cell came in from the west and made a bee line for our house. We got ready to take cover with portable radios, valuables, flashlights, and such but it was over even before it had begun.

Concerned by reports of golf ball sized hail that later was updated to baseball sized hail which finally became tea cup sized hail, we anxiously watched the sky and listened to the TV weatherman. (I refuse to call them meteorologists. First they need to prove they know something about weather).

Turned out that the sky really was not falling. We did not experience any tea cups or even mad hatters falling from the sky. We amused ourselves by watching the weatherman take an unscheduled opportunity to hold an instructional presentation on cloud rotation and if it should be clockwise or counterclockwise.

Meanwhile the emergency ham radio net RACES was reporting electrical flashes on the ground in Fort Worth in the vicinity of Beach street. Five minutes later Mr. Meteorologist was reporting a possible tornado on the ground in Fort Worth. I guess the TV station monitors the RACES net too. Not sure what took them so long to get the information out.

Half an hour later that cell was directly above us. The sky was very dark but had not acquired that monster greenish tinge that usually accompanies a tornado.

The sound of sirens all around and for the first time in a long time the sound was not coming from the TV speakers.

The wind picked up. It picked up a couple of loose leaves in the back yard but did not seem threatening. Gusts to 30 mph at best and big rain drops all over. Nice downpour but the light was getting worse since the sun had set and it was difficult to see much.

That lasted about 15 minutes. The sky got a little darker, then much lighter very suddenly. RACES reports of a possible tornado in east Garland. So the storm had passed and not so much as a twig had been removed from the trees in the heavily wooded area that marks our neighborhood.

Good. Our luck held out just as it has since 1979. Sure happy about the rain. We certainly needed that.

I understand there may be another super dupper cell arrive around the end of this weekend and another later next week. Yup, spring has arrived just like it always does.

Say, you suppose that later this week the weather guy has figured out which way the clouds should be rotating. Not sure we could survive without knowing that!

Regenerative Receiver Hints

April 13, 2007

You don’t know what frustration is until you have tried to use a marginally functioning regenerative receiver as a communications receiver. Then I guess marginally functioning equipment of any type would frustrate the user. It is just that regenerative receivers have so much more to become frustrating.

Drift, hand capacity effects, flakey regeneration control, dial setting jumps when you touch it, headphones are uncomfortable, not sensitive enough normally and when you increase sensitivity, you can’t keep the signal tuned in. Those are just a few of the ‘fun’ experiences you are opening yourself up to.

Here are a few tips on how to deal with these frustrations.

Choose your tuning capacitors and dials very carefully. Ball bearing capacitors and zero backlash dials are best. If it is good enough to be used in building a VFO, it will probably work fine in a regen.

Wooden cabinets are fine but the front panel needs to be made of metal and connected to ground to prevent hand capacitance effects to the circuitry. Any part of the circuit could be effected by hand capacitance, not just the coil.

You don’t need RF amplification but you could benefit from RF isolation from the antenna. A grounded grid triode amp at the input will prevent the antenna from loading down the oscillator.

A triode makes a decent regenerative detector but a pentode makes an even better detector and allows smooth control of the regeneration threshold by varying the screen grid voltage.

The screen grid voltage to the detector needs to be well regulated. Using a VR tube here is a good idea.

Although a pentode detector has good output, it is not good enough to drive a headset under all conditions. Follow the detector with at least one audio stage before the headphones.

If you want speaker volume, then add another audio stage (maybe a 6V6) after the first.

If you have kept up with the tube count we are now up to five tubes. We might want to re-evaluate the design. Maybe go with a single conversion heterodyne.

Run the radio off batteries or a separate AC power supply. With the high sensitivity of the detector it will be nearly impossible to keep hum out of the radio if the power supply is built into the radio case.

You probably decided on a regenerative receiver thinking it would be a simple project. It can be simple but to get decent performance the regen becomes as big a project as a simple heterodyne.

Also, the same problems you experience using a single conversion heterodyne at higher frequencies also plague the regenerative receiver. At the very least, stability will suffer. Even so, both of these receivers can do very well on 80 and 40 meters. There is absolutely nothing wrong with using a crystal controlled converter, making the system a dual conversion, regardless of whether you decide on a single conversion heterodyne or regenerative.

Used Ham Radio Equipment

April 13, 2007

Is it worth screwing with used ham radio equipment? YES! Most definately, but be careful.

Hams are a cantankerous lot. They don’t get rid of stuff that is useful unless they are dealers. Now it could be that the equipment is just old and they are tired of it. If the stuff is new to you and works, it might take you longer to tire of using it.

On the other hand, the stuff could be junk that has been hosed down and dried off so that it becomes presentable.

Unless you can have the equipment demonstrated under actual operating conditions, maybe make a few contacts and get some signal reports, don’t pay more than salvage value.

Even before you make an offer, pay attention to the conditions under which the item is being offered. Don’t make an offer on the stuff if you are confronted with any of the following:

‘I am selling this for a friend’
Could be his ‘friend’ does not even know he has it.

‘It worked the last time I used it’
That might have been 30 years ago when he first bought it new. Chances are good that if it was working, he would not be trying sell it.

‘It is in mint condition’
If he is not a dealer presenting you with brand new equipment with factory manual, box, and warrantee, he is lying to your face.

‘Complete with copy of the original manual’
If it does not have the original manual, it has been orphaned and probably more than once.

‘Power supply and mike are not included’
Might only have had time enough to steal the rig itself.

‘Very rare collectible’
If you are looking for collectibles at a hamfest, you are out of your mind!

You will just not find highly desirable equipment on the bargain table at a flea market or hamfest. That does not mean it cannot be useful but its usefulness will vary from person to person. It all depends on what their needs are.

Lots of old equipment began life in kit form. Make sure if that is the case for the item you are considering that it had life after assembly. An unusually frequent problem is that kits that never worked are being offered as valuable collectibles. Unless you are a junk collector, you may not be interested in such equipment.

Store Brands

April 13, 2007

Certain grocery items can be purchased as store brands. For instance, in the case of a can of peas, the store brand may have Kroger on the label instead of Libby’s.

Store brands are generally less expensive offering five to ten percent savings. Unfortunately, when you open that can of peas, you may discover what was done to offer you the savings over the brand name.

If the item is to be used as an ingredient in a recipe and is just one of many with most of the many being herbs and spices which are mainly responsible for the ultimate flavor of the dish, you may never realize that a store brand was used.

If, however, the store brand item is it, meaning it is the dish itself, there may be greater potential for disappointment.

Some store brand items that have been disappointing have been mustard, pre-cooked sausage patties, some condensed soups, and canned vegetables.

The store brand mustard was thinner, more acidic, and had a funny taste when compared to French’s.

The store brand sausage patties had more fat content and a decidedly gamey taste when compared to Jimmy Dean patties.

The store brand condensed mushroom soup did not seem to be as condensed as the Campbell brand.

Lastly, the store brand canned peas were decidedly inferior to LeSueur brand peas. That may be an unfair comparison. LeSueur peas are the caviar of canned vegetables.

1GIG USB Stick

April 7, 2007

I remember when I considered myself lucky to own a 100mb hard drive. I just can’t remember exactly what year that was but I definately recall that it was NOT FREE.

I just redeemed a card for a FREE 1GIG USB Stick at the Micro Center. One Gigabyte!!!! That is 1000 mb or ten times the size of my 100mb hard drive.

It is hard to understand how they can stuff that much memory into such a small space. The thing is about two inches long and three-quarters of an inch wide. I just hope none of those bytes fall out. I would never be able to stuff them back in again.

It even works on my old win98 machine. Formated out to 967mb. I don’t even feel cheated that it did not format out the full 1gig.

My very first hard drive was in an IBM PC. It was only 10mb worth of storage and cost over $300. It was also the size of a small shoe box and took up a full sized 5-1/4 inch drive bay. That was around 1980.

Had someone told me then that I would be getting a free 1000mb USB memory stick that could fit in my pocket, be portable, and work like a hard drive but not have any moving parts, I would have thought they were nuts.