eHam.net - Amateur Radio (Ham Radio) Community

Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net


Reviews Categories | Amplifiers: RF Power - 6M/VHF/UHF+ | RM VLA200 Help


Reviews Summary for RM VLA200
RM VLA200 Reviews: 14 Average rating: 4.2/5 MSRP: $390 Euros
Description: VHF Linear Amplifier. 50W in and 200 W out.
Product is in production.
More info: http://www.rmitaly.com/scheda.asp?tipo=113&lingua=
Email Subscription
You are not subscribed to this review.

Subscribe!
My Subscriptions
Subscriptions Help

You can write your own review of the RM VLA200.

Page 1 of 2 —>

AB0YM Rating: 5/5 Aug 22, 2015 10:47 Send this review to a friend
Great amp for 2m rover  Time owned: more than 12 months
I bought mine to use in my rover vehicle during VHF contests. I was reluctant to purchase it as there were many negative reviews on RM amps in general. For that reason, I ordered through Amazon. For my requirements, the VLA200, short of designing/building something was the "only game in town". I needed something that would output around 200w SSB, reasonably mechanically rugged, run on 12v, and have low idle current. I do not use the built in preamp, as I already had one inline and I key the ptt.
Glad I go mine while they were still readily available.
So far, it has worked flawlessly. I drive it with an FT857 at about 45w SSB and moderate speech processing. The amp barely gets warm (mine does not have fans).
I am wondering if the operators that had heating problems were running a high duty cycle mode like FM or one of the digital modes.
 
W6LDX Rating: 5/5 Apr 24, 2015 12:51 Send this review to a friend
Extend The SSB delay  Time owned: more than 12 months
To extend the SSB delay take an axial 47 mfd 25v electrolytic capacitor and solder the positive side to R1 side nearest to the C1 33uf capacitor and run a wire from the negative side of the 47 mfd cap to the top connection point of the SSB switch. I put the 47 mfd cap at a 45 degree angle to the board to keep it away from the RF input trace and ran the wire from the negative side of the 47 mfd cap inside a slot all the way to the front where it then was soldered to the SSB switch and used scotch tape to hold it in the slot. The result was no more drop-out between words and a double delay time. You are on your own and I assume no responsibility for anyones mistakes. But, it works great.
 
N9IVQ Rating: 5/5 Nov 5, 2012 18:06 Send this review to a friend
Nice Amp, am please  Time owned: more than 12 months
I have been using a VLA200-1 VHF amp for several years. Bought it used on eBay. If i push it with 35 watts in (FM) it gets 190+ watts out. With 50 watts (SSB) i can get 200+ out of the amp with no proble. 5 watts in I get 50 watts out FM or SSB.

I mounted two CPU fans on the amp to help cool it, but it has never gotten hot so never been a real issue. I am just paranoid. The only other thing I have done to the amp is to add a PTT key line. In SSB the relay is a little slow and drops a lot between words. Tried playing with the timming cap, but no real joy there. Hard to find the "sweat spot"... Relay chatter is anoying. External PTT takes care of that issue.

RX Pre amp does work. Have tested with and without pre-amp and on those long haul VHF extended range contacts it does make a big differance.

All-in-all I am very happy with the amp. Now i would like to try one of their UHF amps...

Well worth the $150 i paid for it.
 
WV4I Rating: 5/5 Nov 2, 2012 15:31 Send this review to a friend
works as advertised ***  Time owned: 0 to 3 months
I say works as advertised *** because manual vs online specs are a bit vague, if not conflicting. However, it's a nice amp in its niche. Fit and finish are excellent. That niche is the owner that only wants 6db RF output gain, from 2 x SD1477 finals, and a receive pre amp BF966S with 18-25db gain at a rated NF of 1.8 to 1.0 db. So for SSB, 25W in gets you about 100W out, max 100W >>> max 400W out. FM, max 50W in, gets you 200W out.

I don't have lab equip, i.e. only a RMS wattmeter for VHF and the amp meter on my Alinco power supply, but this amp is easily in the ball park re its claimed specs.

Again it is actually a max 50W in/200W out for FM and max 100W in/400W out amp for SSB (PEP). Turning on the receive pre amp does appear to raise the signal 18-25db on my S meter. The current draw can get to 28A on my power supply, not 24A, but mine has fans, doubt they draw 4A however. There are no fuses on the power cord, but the amp is fused internally, shows 2 x 12A fuses in parallel.

I have also owned Mirage and TE Systems 2M amps, so can make a comparison.

If you look at the Mirage manual for their B2518G amp that touts 160W out, that is for FM, not SSB. SSB, it's a 100-110W PEP amp with 25W in, 6 db gain, more and you're splattering, non-linear, etc.. Almost same price as the VLA200, but only capable of 1/4 the max power out on SSB. Both have receive pre amps, similar gain/NF. So if your 2M exciter/xcvr does more than 25W PEP on SSB, this would suggest that the better choice is the VLA200, up to 4 x max power out at same cost.

Then there are TE Systems amps, the 1452G in particular. It's around double the price of the Mirage B2518G and RM Italy VLA200, for several reasons. First is the gain. The 1452G will really do 350-400W PEP SSB with only 10-15W in, no kidding, and back when I did have a PEP wattmeter for 2M. This does take about 54A at 13.8 VDC. Talking an RS-70M PS or similar at $300+ just to power the 1452G. The TE also has a better pre amp with an advertised NF of just .5 DB. Many times the RF gain of the half priced units, and looks mil-spec.

Lastly is the hard keying vs rf sense keying of the VLA200, any amp with a receive preamp. It will do both but with pre amp on, if the relays don't get sequenced/sensed properly, so to speak, you'll blow the BF966S rx preamp device in an instant. To hard key this amp, it simply needs to see its "PTT connection" grounded, and be in FM mode, regardless of actual mode in use. This connection on the amp is a female RCA plug, so your keying line from transceiver has to terminate obviously in a male RCA plug, also not in manual.

Well obviously the documentation needs work, but overall, this amp is a far better value than its obvious Mirage competitors, especially if you have more than 25W PEP drive available on SSB. The TEs are nice, but cost $700 new, are a tough sell in the $500s used, but high quality and far superior specs. It's only money.



 
KB0OU Rating: 4/5 Oct 4, 2012 12:25 Send this review to a friend
2nd one works!!  Time owned: 0 to 3 months
I ordered the VLA-200 amplifier on Sept. 5, 2012 through Amazon.
I received the first amplifier and installed it in my Ham Radio Station and without even keying it up it started oscillating all on it's own. I sent DNJ Radio the following message "Amplifier goes into oscillation when not in use. Does it when the On Switch is On or Off, with power applied to amplifier. Can disconnect radio and continues until power is taken away from amplifier.
Please advise what to do with this problem."
They asked for my phone No. and I got in contact with DNJ and got an answereing machine.
Finally got in contact with a real human and they sent me a UPS label to send the amplifier back.
The amplifier was sent to Pennsylvania on 9/20/12, when it got to Pennsylvania it was left on someone's front porch.
DNJ supposedly had a technician check out the amplifier and this is the report I got....
"our tech guy tested amp. It seems to go into self oscillations, usually caused by shorted finals. Output is low, Even at point of saturation!! sometime taking these 100 watt radios and over driving FETs. 25 watts seems to be safe on SSB 20 watts FM normal operation . these transistors are OK from factory the only way they short or open is from to much current or excessive voltage, when you get the new amp, please don't over-drive it ( I am not saying you did last time ). thanks.
DNJ Radio"
Note: I run a FT-847 radio that is rated at max output of 50 watts on 2 meters, Don't know how I overdrove the amp.?????
At least they did send me a new amplifier after the bad one arrived in Pennsyvania, note,,, they are shipped from California.

Bottom line is that I do now have a good amplifier, I have had it since 10/2/12 Evening and it has worked fine so far. So, they did follow through on the warranty, one always wonders about those things. That is one reason I ordered this amp. through Amazon.com.
 
W1WN Rating: 5/5 Jul 10, 2012 09:44 Send this review to a friend
Excellent product  Time owned: 0 to 3 months
Received the amp and have put it through its paces. 5 watts on the 2 meter radio produces 50 watts out. I use it on the medium setting (25 watts) and get a solid 200 watts output. Fans are nice and keep it cool. Would not use high power on the radio to key the amp up as per other comments. Well made and attractive looking. Seems to do everything that was promised.
 
KJ3LR Rating: 5/5 May 28, 2012 03:36 Send this review to a friend
So Far So Good  Time owned: 0 to 3 months
A really nice PA for FM or SSB.
I use mine (without the fans) for repeater use.
I am using roughly 1/3 of the amp's 200 watt capability. Also using an external fan for cooling.
So far, the RM VLA200 is performing pretty good.
Customer support is outstanding from DNJ Radio, one of the state side dealer's for this PA.
 
VK3DXE Rating: 4/5 Feb 28, 2012 06:44 Send this review to a friend
A good workhorse at a reasonable price  Time owned: 6 to 12 months
Mine is the /v model with the fans. Similar specs as the THP HL-200V50 (same 2 x SD1477 power devices) at a significant cost saving. BF966 preamp. Although I'm not sure if it achieves the 1dB noise figure this device is capable of, it performs adequately for general weak signal work. I've had a number of EME contacts on JT65 with this unit and it performs nicely - 30w in = 200w out. Worth the effort to set it up properly as it WILL draw in excess of 35 amps at 50w input - a recipe for a short life for the power devices. Will run all day on SSB with 50w in, but I keep the wick wound back on digital modes.
 
VK7HDX Rating: 4/5 Sep 6, 2009 05:06 Send this review to a friend
Good so far  Time owned: 0 to 3 months
I tend not to overdrive RF amps but a steady 15w seems to make the all the LED lights dance across the device. I'm sure you could drive a bit harder.

The RX amp is good as well.

I have the VLA200/V version. Which has twin fans on top....

73..Karl
VK7HDX



 
W4AIJ Rating: 4/5 Mar 12, 2008 21:21 Send this review to a friend
Good AMPs  Time owned: 6 to 12 months
I own 3 different RM amps and have not experienced any problems. I do not drive them to full output as most will do, trying to squeeze every last watt out , then wonder why they burn up. Workmanship is much better than the more expensive American amps with better soldering attention to detail. They'll last forever if NOT ABUSED .
 
Page 1 of 2 —>


If you have any questions, problems, or suggestions about Reviews, please email your Reviews Manager.