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Hello Ryan,
170ma is a fair rx current for FT-857. Another test is to set the radio to SSB and key the radio without any audio into the mic. You should see the Tx current with the idle current into the driver and finals. This should be 3-4 amps.
It’s possible you are looking too hard at batteries and charging circuits. If you have around 13 volts measured at the radio’s DC connector there is no way those items can effect the amount of current the radio consumes.
If the 13V is there during Tx and the current (and therefore RF power) is low I would suspect the radio is folding back due to a high antenna SWR.
If you are monitoring current while TXing SSB at 100w the current will be far less than 20A unless measured with a peak reading meter or o’scope due to the low duty cycle of SSB. I suggest using FM or CW since they are both 100% duty cycle.
73
Hamilton
Just a note on Niece’s weekly sloooow CW net. All are accepted from 0 wpm up to 5 wpm. If you can tap out your call sign you can copy using AIM in net logger. Many boobies lurk for weeks before they jump in.
SLOW CW NET SUNDAY 8 pm est freq: 7.045 netlogger.org
K1ULN – Please confirm all qso’s
BLOG: KA1ULN.BLOGSPOT.COM
Hello Bob,
We are all different, for me the best choice was a paddle. I bought a used Bencher BY-1 off QTH for around $60. I also started practicing with my left hand due to a mild tremor in my right. I’m right handed. Letting the keyer handle the dit, dah, and space lengths let me focus on what I was sending.
I found sending to be easy. In a few short weeks I could send well with almost no prior experience. Learning to receive took two years before I had a basic skill and another two years to feel comfortable.
I sold the Bencher and got a Begali. I like the Begali but I can say you will be fine starting with the BY-1 or similar.
I found lcwo.net to be very helpful to learn to receive.
Now on the lighter side 6 months after I got my license and before I ever touched a key I worked CW at my first field day. I set up the 80m CW tent and Fred gave me a couple pointers. I logged a number of CW QSOs at 2 points each. There is an article describing the experience on this site… With 6 months to get ready you will do fine.
73
Hamilton K1HMS
Hello Burns,
A lot of us get commercial cards that are printed on one side. We use DX Lab or other logging program to print the QSL information on the backside as well as addressing the envelopes. Glossy color QSL cards cost about $70 for 1000. (blank on back)
About 20% of the cards I receive are plain white or colored 3×5 index cards produced the same as above. Some OM will preprint the cards with some art (e.g. ARRL logo), their name, address, and other fixed data. The QSL info is then printed on the card or Avery labels. The card is sent in a envelope.
You might consider the postcard approach. Anything mailed must be 3-1/2″ x 5″ minimum else the USPS will reject it so 3×5 index cards are not acceptable without a envelope. A typical QSL card is 3-1/2″ x 5-1/2″, a bit larger in Japan, rarely larger than 4″ x 6″. Blank postcards from Staples or similar are typically 4″ x 6″.
If I want to send a large number of QSL cards and I’m not requesting a card back I will use postcards, with a small twist. Instead of printing on the cards I will print Avery labels for the QSL info and also for the addresses.
73
Hamilton K1HMS
Hello Marvin,
Grounding laptops can be difficult. I occasionally see radios with USB issues likely due to someone with a good static charge touching the laptop. The charge is terminated at the USB circuit in the radio.
Here are a few steps that can help minimize the risk:
1) Check the resistance between the shells on your USB cable. Even with probe and contact resistance a good 6′ cable will have 2 ohms or less of resistance. When I first became aware of this I went through my collection of cables and found R over 20 ohms to no connection at all in 1/3 of my cables. A good cable will provide an adequate connection.
2) Make sure the charger (or a PC) is plugged into the same surge protector as the rest of the equipment. If there are monitors make sure they are also plugged into the same surge protector. Monitors can provide a significant current path from the laptop, on its own a laptop has a small charge “mass”.
3) The first two will likely prevent damage from a large ESD spike. The next step is a USB surge protector. It would be inserted in the cable near the radio with a short cable from it to the radio. The shell of the protector would have a wire to the radio’s case. These are available from L-Com and others and can be expensive. They have TVS diodes on all 4 lines to ground. Do not use a galvanic isolator, they do not support USB 2.0 speeds and the DC isolation does nothing for high voltage AC spikes.
Did you see the related post from last week?
Hamilton K1HMS
Hello Marvin,
You have found a likely source of the voices that occur in random parts of a FT8 RX period. I initially thought they were Lids trying to jam or a strong phone signal leaking through.
System sounds will “play through” if they are not disabled.
Often the voice is near the start of multiple 15sec receive periods. The odds are low they were system sounds due to timing. Radio voice messages or something like a MFJ voice keyer would occure right after the start of TX.
If the OM has “fake it” or split enabled there would be a frequency called out at the start of TX.
73
Hamilton
Hi,
Key to grounding is to ensure everything is at the same potential. There will be zero current between two wires that are at the same voltage. No current, no damage.
If you ground the AC surge protector which uses MOVs to connect all it’s wires together and to ground, the antenna shield with a coaxial surge protector to connect the center conductor to ground, and if used, all 8 of the rotator control line to the same ground with MOVs and possibly GDTs then everything is at the same potential during a strike.
This is extended to the radio and computer by grounding their cases together and to the common station ground. This process of tying everything together is called bonding.
If this is all there is the equipment would survive a 2KA spike. Note that even a strike on the power grid, which is likely, will appear on the AC surge protector at the station ground and via all of the MOVs and GDTs will result is a equal potential on all of the lines, including the antenna and rotator.
Where the damage occurs is when paths outside of the “bonding” are introduced.
As an example everything is bonded except the computer or monitors are plugged into a wall plug and not the station surge protector. There is a USB cable between the PC and radio. During a strike on the antenna the radio will be at many KVs, the PC grounded back at the service entrance will be near zero V. The potential difference will be across the USB cable and the current through PC/radio circuits. The same is true if the strike is on the power grid and the current is flowing to the station ground.
<p style=”text-align: left;”>Lightning has a broad RF spectrum. A larger conductor will have more surface area to reduce skin effect and will have a lower inductance.</p>
The ground wire 60′ across the basement to the service panel isn’t directly part of station bonding. The strike will be over before the service panel end of the wire will reach its peak voltage. It will help to mitigate the damage to everything outside the operating position and provide protection from AC ground faults.I see a radio every few weeks with lightning damage. Damage to USB devices is most common, the DC power input circuit is second, both likely due to power line strikes. The RF input is last, but typically has the most visible damage with missing parts, melted relays, and burnt traces.
The take away is to eliminate potential voltage differences and to watch for stray paths, this includes the desk lamp next to the radio.
Hello John,
That may well be the cause. I cannot tell what it is saying. As I wrote it does sound like an announcement. It is always at the start of the cycle and is only a few words. It fits with a radio’s announcement.
Most newer radios have a monitor function so you can hear your transmission.
73
Hamilton K1HMS
Hello Frank,
I know exactly what you are saying but have no idea where it is coming from.
It sounds like a man making an announcement during the first few seconds of FT-8 reception. It only happens occasionally.
I thought I had a station problem but gave up looking for a cause. Also I have a TS-590SG so it isn’t unique to the 7300.
I’ve wondered if it isn’t some lid having some “fun”.
Tom may be on to something. If someone had one of those $10 eBay USB/CODECs that make announcements they might not know what we are hearing. The next time I hear it I’ll switch to the opposite time slot to see if it goes away.
Maybe someone will tell us what it is.
73
Hello Jamey,
There are two differences in the measurements.
The one that I would track first is power. The analyzer is <10mW, the 7100 is watts. If there is a near short such as a stray ground braid wire or a insulator O ring that is off center it may cause a problem at higher power.
Try reducing the 7100’s power and remeasure. At minimum power the SWR reading may be off a little, that isn’t important for the test.
The second item is the 7100 is grounded to the vehicle, I doubt the analyzer was. The antenna and cable as a system may be 1.2:1 but once the cable end is grounded at the radio it may be different.
Try touching the connector at the analyzer to ground and observe the SWR. If it changes significantly you found the problem.
I can think of a couple of other possible causes but they are a stretch.
Let me know how it goes.