Many thanks to Pat (N0HR) who shared following question in a comment:
Thomas
I simply love your videos – both your impressions of the gear and the activations themselves. Great stuff.
I’m curious – now that you’ve played with both the SW-3B and the Penntek TR-35, which is the favorite? Seems like they’re both roughly in the same price range.
Thanks for your fantastic channel and website
73, Pat N0HR
Thank you for the kind words, Pat, and great question! Several people have asked me variations of this very question recently.
I like both radios, so I’ll frame this in a way that might help others make a purchase decision.
I pushed the last field report and activation video to the front of the line so that I could show how CW message memory keying worked in the TR-35’s updated firmware. It was, in my opinion, a major upgrade!
What follows is my field report from April 1, 2022: my first POTA activation with the Penntek TR-35. This video was made a week or so before I learned that WA3RNC was working on the new firmware.
Although I’d used the TR-35 in the shack for more than a month I was eager to find an opportunity to take it to the field. April 1, 2022 was that day and I made a little detour to one of my favorite local POTA sites to break in the TR-35… Continue reading Field Report: My first POTA activation with the Penntek TR-35→
Since I have a busy family life, I always look for opportunities to fit a little field radio time into my schedule.
My policy is to always keep a radio field kit in my car or truck so I can take advantage of any last minute opportunities.
On the morning of Wednesday, April 20, 2022, I was scheduled to take my car in for warranty/recall servicing at the dealership. I decided in advance that if the service could be completed in two hours or less, I’d relax in their waiting room with my MacBook, drink a cup or two coffee, and attempt to make a dent in my email backlog.
If the service was going to take longer than 2 hours, I decided that I’d use one of their loaner/courtesy cars and activate a nearby park.
The dealership is about 45 minutes from my QTH and I’ve activated most of the parks nearby it, save one: Holmes Educational State Forest. I’ve been wanting to activate this park for ages, but my travels these days simply don’t take me in the direction of the park very often; it’s a good 75 minute drive from my QTH.
Uncertain how long the dealership would need my car, I grabbed my SOTA backpack that had a full field kit inside based on the Penntek TR-35 transceiver.
TR-35 Upgrades!
Why the TR-35? Because I was testing new firmware that added a huge upgrade: two CW message memories!
Suffice it to say, I was itching to see how well the new message memories work during a proper activation.
Front of the line
Since this upgrade was just made public, I thought those of you who either own the TR-35 or are plotting to purchase the TR-35, might want to see it in action. For this reason, I pushed this video and field report ahead of all of the others in my pipeline.
The really weird part about publishing this video so quickly is that one of my next field reports and videos will actually feature the first time I took the TR-35 to the field about 3-4 weeks ago! Back then, CW message memory keying wasn’t even on the table.
Activation time
I arrived at the dealership around 9:00 AM (local) and the first thing I asked was, “So how long do you think this will take?” The representative looked at the work to be performed and said, “Three or four hours, likely. If you’re in a rush, maybe two hours.”
I decided I wasn’t in a rush because I’d much rather be playing radio at a new-to-me park than sitting in a waiting room.
I asked if I could borrow one of their courtesy cars and he replied, “We assumed you might want one Mr. Witherspoon, so we already reserved one for you.”
John (WA3RNC) has just announced a new firmware (V.0.24) upgrade for the Penntek TR-35 that will start shipping in all TR-35 orders starting Sunday April 23, 2022.
The new processor adds two new features:
The ability to record and playback two CW message memories
A function to toggle the display from black with blue characters to solid blue with black characters
Of course, the big upgrade–in my world–is the addition of CW message memory keying and I can confirm that it works very well. More on that below…
Obtaining the upgrade
As John (WA3RNC) states in his announcement:
The good news is that any TR-35 can be upgraded with a simple replacement of a properly programmed plug-in microprocessor, or with the reprogramming of the original microprocessor. No other hardware changes are required.
But…there is bad news. The availability of the Atmega328P-PU microprocessor has gone from “buy it anywhere for $1.95″ in mid-2021″ to “virtually unavailable anywhere at any price” today. Delivery dates are quoted as May of 2023 for orders that I placed last year.
[…]Because of this critical chip shortage, I do not have a sufficient inventory of the Atmega part to be able to send out programmed microprocessors for upgrades. What parts I do have are destined for production of TR-35 and TR-45L transceivers.
Therefore, a TR-35 firmware upgrade will require that the transceiver be sent to me freight prepaid for reprogramming, along with funds for return shipping and insurance of $15.00.
Understand that there is no charge for the actual upgrade reprogramming, only for the cost of returning your unit to you.
I think is excellent customer service, actually, and a clever way to get around the chip shortage: use the chip you already have.
Again, if you’re buying a new TR-35, it’ll ship with the latest firmware.
If CW message memory keying or inverting the OLED screen colors aren’t important to you, it’s not necessarily worth upgrading because the new firmware only includes the new features.
Testing message memories
Recently, John sent me an upgraded chip with an early Beta version of the new firmware to thoroughly test in the field. I replaced the TR-35 chip myself.
I tested the new functionality in the shack and on a dummy load.
As with most built-in CW message recorders, you’ll need to set the CW speed to a comfortable setting before recording. During the recording process, you need to send accurately spaced characters, else, for example, the software might interpret the “AN” in your callsign as a “P.”
The first time I set memory 1 to “CQ POTA DE K4SWL” it took three tries to get it right. When I set the second memory to “BK TU 73 DE K4SWL” I recorded it in one go.
Recording message memories on the TR-35 is at least as easy as directly recording a message on my KX2 or KX3. I’m pleased.
In the field
Last week, I took the upgraded TR-35 to the field and used the message memory keying during my activation.
It worked beautifully.
John sorted out a clever way to initiate playback without having to make any hardware additions to the radio:
To play a message memory, simply tap the AUX switch down and then hit the left side of your paddle to send message #1 or the right side to send message #2.
Recording messages works the same way, but instead of a short press of the AUX switch, you initiate a long press.
Even this early version of the upgrade worked well.
Field report and video coming soon!
I’m going to push the field report from last week to the front of the line because I know many of you will be curious to see how it plays in the field. Hopefully, I can post this by Monday (April 25).
My Penntek TR-35 Review
FYI: My full review of the TR-35 will be in the May 2022 issue of The Spectrum Monitor magazine.
I found this case at Harbor Freight [see above]. It adds weatherproofing and I put in a 3D printed key I make and cables and a pen and notepad for logging and copying CW.
FYI: Joe is the kit building editor at CQ Magazine where you’ll find his many excellent articles. In fact, he’s featuring the TR-35 in his April column at CQ Magazine.
I read with interest your posts about the PENNTEK TR-35 and liked it enough to go ahead and order one for myself. I built it over a couple of weekends of occasional work, and put it on the air. I really like it.
Since I’d like to take it out on some POTA activations, I did some investigation into a case and found the following case on Amazon:
This case fits the TR-35 very nicely. See the attached photos.
There is even room for a couple of cables to be tucked away under the mesh on the lid side. The only modification I made was to add a couple of pieces of packing foam around the top and BNC side to just keep the radio from sliding around a little. But really a person preference of mine.
I thought I’d share this with you so you can share with others that have this radio and are looking for a nice hard case.
Mark
W8EWH
What a great tip, Mark! Looks like it fits the TR-35 perfectly. Thank you for sharing this!
John reviews both the build and performance. He even put the TR-35 on his workbench and measured a number of parameters.
In short, the little TR-35 does exactly what it sets out to do and packs a surprising amount of performance.
John and I actually had a TR-35 to TR-35 exchange a few days ago (if not mistaken, the photo above was taken after that exchange). I was lucky enough to catch him as he activated a POTA site in Texas. From this end, his TR-35 sounded fantastic.
I’m putting together a review of the TR-35 which will likely appear in the May or June issue of The Spectrum Monitor magazine. I’ll eventually send this little TR-35 back to WA3RNC (it was very kindly sent to me on loan) but I do plan to purchase his TR-45 Lite kit when it hits the market later this year. Why? Because I don’t have enough QRP radios, that’s why.
Good morning Thomas, from wintry southwestern Ontario.
I thought I would send you a quick message to share my experiences, so far, with the little TR-35.
Yesterday, around 3pm, I took the above unassembled kit off the shelf and began to melt solder. The smoke test was successfully performed the next morning at 1:30am, after non-stop building (with the exception of a few hours for eating and catching up on a little tv). I measure twice and solder once hihi.
Many thanks to Jim (N9EET) who notes that WA3RNC will soon be shipping his latest QRP transceiver kit: the TR-35.
According to the WA3RNC website, factory wired/assembled kits are available now for $379 US. The regular kits (with pre-wound toroids!) will be available for purchase January 24, 2022 for $279 US. If you’d like the pre-assembled version, simply click the checkbox that adds $100 for assembly in the WA3RNC store.
Here are a few TR-35 specs from the WA3RNC website:
Size 5 ½ X 3 ¼ X 1 ½ less protrusions, weight 10.6 Oz
5 watts output on all bands at 12vdc input
Full coverage of 40, 30, 20, and 17 meters with extended RCVR tuning above and below
RCVR modes for CW narrow and CW wideband, and for SSB reception
Optimized for operation from 3 series-connected 18650 Lithium cells
RIT tunes + and – 5KHz
Blue OLED display reads frequency to 10 Hz and RIT offset
Built in Iambic keyer is adjustable 5 to 45 WPM with front panel control
Separate jacks for straight key and paddles; Always ready for SKCC contacts
Operates on 9.5 to 14 volts, < 100 ma receive, about 1 Amp Xmitt at 10 volts
Selectable tuning resolution steps of 10, 100, and 1000Hz
Low battery indicator with internal adjustment 9.5 to 11.5 volts
Front panel adjustable RF gain control
Front panel TX power control; Adjustable from 0 to full output
Rugged TO-220 FET RF amp has delivered 5 Watts key down for 5 minutes
Signal quality blue LED, RIT warning orange LED, Low battery red LED
Excellent receiver sensitivity with MDS of -125dBm
Very effective receive AGC prevents ear damage with strong signals
Transmitter harmonics and spurs -52dB, meets FCC specs
CW sidetone is the actual transmitter signal as heard by receiver
Match the received signal tone to the sidetone for perfect zero beating
Sharp IF filter; Better than 350 Hz at the -6dB point, plus 700 Hz audio filter
Over 250 machine placed SMT parts, and about 55 user installed parts
All critical circuits are factory pre-aligned and calibrated
No endless “back menus”; There is a control or switch for every function
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Many thanks to Pat (N0HR) who shared following question in a comment:
