Manager


Manager - NA4M
Manager Notes

Reviews For: LDG RT-100 Remote Tuner

Category: Antenna Tuners/Matching Networks

eMail Subscription

Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted.
Review Summary For : LDG RT-100 Remote Tuner
Reviews: 30MSRP: 199.95
Description:
The RT-100 uses the same proven technology as other LDG tuners, but is engineered to be installed outdoors near the antenna feedpoint, reducing potential SWR losses in the transmission line. DC power is provided over the coax; no separate power cable is required. The RT-100 contains an internal “Bias Tee” circuit that separates RF and DC at the tuner
Product is in production
More Info: http://www.ldgelectronics.com
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00304.1
K6GB Rating: 2016-06-03
Does the job I needed doing. Time Owned: more than 12 months.
I used this particular tuner because it covers 6. I am using it on a TGM mini-beam and it allows me full band coverage and it's small enough to mount on the boom.
KE0EBP Rating: 2016-06-03
Does what it is made for but you must understand it's limits Time Owned: 3 to 6 months.
One caveat, this is my first autotuner adventure (I do have several manual tuners of different types I use). I bought the RT-100 without the separate LDG ST-100 bias T box thinking I was going to make a simplified very portable all-band QRP station built around my Flex 1500 SDR radio and a laptop. To that end I built a home brew “rig buddy box” the same size as the Flex rig to consolidate other needed auxiliary equipment that included a intermediary 15 volt NiMH battery pack (to keep power lines short and prevent high current voltage drops) along with muti input power connectors to keep it charged, a simple Norcal led SWR indicator (dip the LED to indicate the lowest SWR) to keep track of the remote auto tuning status, and push button bias T power out the coax to feed the RT-100 itself but set up to only remote tune when it was actually needed for changing bands without draining the nattery pack(s) (the latching RT-100 relays were a nice touch there). After I got the buddy box all built and tested I went ahead and hooked it into a home brew 9:1 balum feeding a end-fed wire tuned to 40 meters and let it rip. The tuner has some “undocumented features” (it can lock up and need resetting and just sit there otherwise, and will chatter endlessly if it cant find a tune) but for the most part it tunes the 40, 30, and 20 meter bands within a second or so to about 1.2 to 1.6 SWR and 24, 12 and 10 meter bands to about 1.8 to 2.1 or so. 15 meters seems to be that odd man out and will not tune, but I know the wire is cut a bit too long and it's strung around my small second story condo deck with a inside counterpoise (thanks to HOA rules) so the setup is a bit funky at best. In the 15 meter case the RT-100 just keeps “chattering” away and never resolves the tuning as mentioned and never gets under 3:1 SWR, so I can see why some complain about no real status indicator built into the RT-100 (I use a standard SWR meter to back up my home brew Buddy Box LED SWR indicator for testing). I plan to put a 1:1 coax balum in the system before the RT-100 to keep the stray RF out of it and recut the wire better to see if it will make the remote tuner happier on all bands as well as trying it out on a home brew “Kid” Cobra multi band antenna soon. I'll update this as needed.

In my opinon the LDG RT-100 works pretty much as advertised. As pointed out elsewhere having some kind or remote SWR indication would have been nice, but then that would add complexity and cost to what is in fact a reasonably priced wide range bare-bones simple remote tuner you pretty much leave outside clamped to your antenna mast and forget about after you have done the initial setup to a appropriate muti-band antenna. And if you keep that in mind the RT-100 will not disappoint, and I would certainly recommend it to others under those circumstances. (Tom Mengel, KE0EBP)
G4PNF Rating: 2016-04-20
Excellent and reliable 2 years on. Time Owned: more than 12 months.
I have had the LDG-100 in operation for over 2 years now. I have it mounted externally but protected from the worst of the WX in a plastic box. I have it set up on a random length doublet (about 215 feet) with a random length of 300 ohm ribbon feeder, and a 4:1 current balun before the tuner (and about 100 feet coax from tuner to shack). It tunes all bands from 80m to 6m with a low SWR and will give me a reasonable SWR on top band too. There are a few idiosyncrasies with this tuner which others have mentioned.... like it's tendency to retune sometimes even though a perfect match had been found. It is also a bit slow to find the match when it doesn't have a memory of the frequency or the match has changed (like when it rains sometimes!) but overall I think it is a really solid bit of kit. Once you get used to the way it works you can rely on it to do the job. There doesn't seem to be anything else out there that does the same job as a remote in-line coax in/out tuner and I would certainly get another one if I needed it.

----------------------
Earlier 5-star review posted by G4PNF on 2014-01-18

Its early days but having had this little tuner a couple of weeks or so here are my first impressions. I have it connected to a G5RV via a choke balun and it matches well with almost a 1:1 SWR from 80m to 6m including all the WARC bands and 60m. It is pretty quick to find a match once it has "remembered" the frequency but occasionally needs to go through a full tune cycle for some reason. I use it with the RC-100 bias-T unit which also seems to do the job very well indeed.
I do quite a bit of CW at 100 watts and even after a long QSO there is no apparent warming of the unit.
I often find that I need to send a continuous carrier to get it to tune up as the short pulses from CW don't always do the trick. It does however detect low levels of RF and I find a short 5 watt burst of carrier is plenty to operate the tune up process.
Really great so far and it does exactly what I hoped it would do. Looks like LDG have produced a winner.
VA3PCJ Rating: 2015-08-26
Good multiband (HF & 6m) remote tuner Time Owned: 0 to 3 months.
I needed a remote tuner to tune a 43' quasi-vertical wire in HF bands (80m-10m) both with QRP power and QRO up to 100W. The SG-237 Smart tuner failes to tune with QRP power and the Elecraft T1 is rated at a maximum power of 20W. The RT-100 does readily respond to both QRP or QRO RF and, in that respect, it gets the job done. However, I did not give it a top mark because the memory for fast tuning seldom kicks in, and because the best match atatined usually is at an SWR value of 1.7:1, with 17m tuning only at 2.0:1.However, these relative SWR values do not seem to significantly affect the output signal. Overall, a god remote QRP/QRO remote tuner.
K4TB Rating: 2015-07-20
It Certainly Helps Time Owned: 3 to 6 months.
I've had basically the same experiences with memory tunes as K1ZH described in the previous review, however I do appreciate the fact that the RT-100 matches my antenna on all bands 40-6m, given my circumstances. I am using a 33' Eagle One vertical with no radials, only 3 ground rods. I've used the RT-100 and Eagle One with both my transceivers, an Icom 7600 and a Yaesu FT-897 w/LDG AT-997 Plus tuner, with similar results. After tuning up in a band I can easily move around and find a quick memory match but once I change bands it takes several seconds to find a new match even though I've tuned up there before. Nevertheless it matches nearly everything, bringing the SWR well below 1.5:1 with the worst case about 1.7:1. Interestingly, I can then turn off the RT-100's power and while the tuner retains the last setting, I can turn on the transceiver's own tuner and quickly do a final match down to 1:1. I don't know if the last step stresses the RT-100 but so far no problems. I definitely notice an improvement in received signal strength once everything is tuned, as well as better results when I call stations. Therefore, I consider the RT-100 a useful and effective device. I expect that when I add ground radials for the different bands the RT-100 will be able to work even better.
N4KXO Rating: 2015-05-15
Really works Time Owned: 0 to 3 months.
The LDG RT-100 in line with the RC-100 really works. I am using it with my LDG 18 foot vertical at the end of 100 foot run of coax and a 4:1 UNUN. 20 thru 6 meters with no problems. LDG got it right with this product.
K1ZH Rating: 2015-05-11
Same problem as KE2N describes. Memory does'nt work, at all. Time Owned: 3 to 6 months.
I have never seen an "instantaneous band" change as their marketing material suggests. I emailed their support - a complete wasted effort. Below is the exchange I had with them.

K1ZH wrote:
I have a question regarding the tuner memories of the RT-100. Do they, in fact, exist? I ask this because since purchasing (9-23-2014) from CheapHam then installing the unit, I have never witnessed an instantaneous tune from memory. Don’t get me wrong, the tuner works to tune the S9V43 on every band just fine, it just never tunes from memory. If I tune the antenna on 20m at say 14.200MHz, I can see the SWR meter start high (e.g., greater than 4), and then fairly quickly fall in steps to below SWR=1.5. The whole process takes about 5 seconds. Then if I switch bands to 40m and tune up at say 7.200MHz, I see similar tuning adjustments by the RT-100. The problem in my mind is that if I switch back to 14.200MHz and tune, I will see the exact same results as when I tuned not 30 seconds earlier - a 5 second search for the L-C combination. Shouldn’t the memory allow, as you state in your marketing material, an “instantaneous band” change? Is my tuner defective?

LDG Support response:
It should be a little quicker than that. However, if the tuner does not think the match was good, it will not store it in memory. Also if it thinks the memory that it recalls is not good, it will do a full tune. It’s most likely not defective.

W9PMZ Rating: 2015-02-10
Does work mostly as advertised Time Owned: 6 to 12 months.
I mounted it on my chimney with about 50' of wire.

It tuned 40-10 without any problems and I could make contacts.

Would not tune 75M.

I like the feature where the matching stayed at the current setting with the unit turned off.

I did not like how long it took to tune at times.

DC injector was nice, but not really designed to be on the desk top with the RF connectors. Optimal design would have been a box with an on/off switch that goes to the actual DC injector box that sits remotely.
SM0WRA Rating: 2015-02-10
Good tuner, fragile control unit Time Owned: 0 to 3 months.
Update of my first review: the tuner works good within its specifications, which are a bit limited compared to my Elecraft KAT-100, running a benchmark test close to my transceiver. It however tunes my 32 foot vertical all bands 80-10 m within 1:1,7 SWR.
N.B. don´t use it connected directly to your Elecraft 100 KPA amp, which has a 100 uH choke across its terminal to protect the amp from high-voltage sparks. It was probably this connection/choke by pass/ that blew my RC-100 control unit. The control unit is fragile and to my mind needs a redesign. It should first of all include protective circuitry (e.g.a 500 ma fuse) and more robust inductors L4-L7. You may better off building your own bias-tee, which I did for less than 12 dollars.
Finally, sorry to say that LDG technical support is inadequate and can only sing one song,¨send it to us¨. This is prohibitively expensive for us living outside the US. They provide no help for fault tracing and will not give component specifications. I give them only 1, they answer but give no useful help. Instead a give a 5 to Daniel with their german distributor WIMO for hands on and practical advise. 73 Per SM0WRA
N9AOP Rating: 2015-01-22
As Advertised Time Owned: 3 to 6 months.
Bought in August and used weekends in my camper to tune a shakesphere 1020 antenna with a 4:1 UNUN and KX3. As with any remote coupler, you have to make sure that whatever you are trying to tune falls wirtthin the parameters of the unit. I have used other LDG tuners and they all worked well for me. I am currently using it at the base of a tree with 53 ft of wire, a 9:1 UNUN and 4 radials. I am not in a restricted community but if I were, this thing would be invisible.