|
New to Ham Radio?
My Profile
Community
Articles
Forums
News
Reviews
Friends Remembered
Speak Out
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 Summary for Dentron GLA-1000 |
|
Reviews: 7
|
Average rating: 3.0/5
|
MSRP: $1
|
|
Description: 10-80MTRS 1200W INPUT HF AMP
|
|
More info: http://
|
|
You can
write your own review of the Dentron GLA-1000.
|
PA0FRI
|
Rating: 4/5
|
Apr 19, 2007 05:34
|
Send this review to a friend
|
|
Great for homebrew
|
Time owned: more than 12 months
|
Indeed, this is a great little amp for those who have the time for projects but pay max. $150 for a mint GLA-1000. As an experiment I have converted this beauty over to EL519 and later on with two Russian GI7B’s in parallel using the orginial transformer but with a voltage doubler, and an added 12.6 filament transformer.
For more details see: www.xs4all.nl/~pa0fri/Lineairs/GLA1000/gla1000eng.htm.
|
|
WA7VTD
|
Rating: 2/5
|
Apr 18, 2007 20:52
|
Send this review to a friend
|
|
Great for a Project, Lousy As-Is
|
Time owned: 0 to 3 months
|
Great amp for those who have the time for projects. Lousy amp for those desiring a small-footprint, RELIABLE desktop amp of moderate power output (a half kilowatt).
Wonderful descriptions of, and plans for, the upgrades, tube conversions and circuit improvements for the GLA-1000 have been graciously posted on the Web by numerous hams. The various improvements and conversions range from easy to moderately complex, and from quick to several evenings/weekends, in difficulty and time intensiveness.
This is a really good amp for somoene who either loves to work on/improve/restore amps, or who wishes to learn hands-on about good and bad amplifier design. As a project piece, it provides the basic platform and components for eventually having a quite compact and reliable little amp.
If however, you aren't project-oriented in the amp purchase desire, and are simply looking for a plug-and-play amplifier that will last, skip the GLA-1000. It (barely) gets a "2" from me based on that aspect. There were too many design shortcuts and this amp is guaranteed to fail at some point. A used FL-2100B, SB-200, or AL-811 would, in my opinion, be a much better investment for a medium-powered, relativey small, 20-25-year-old desktop amp, and the latter three also utilize fairly inexpensive tubes and will be true workhorses if shown proper care. (The SB-200 should also have some mods performed in order to render it compatible with solid-state rigs and to improve tube longevity, prevent destructive parasitics, etc.; there are kits available for that purpose and a well-built SB-200 also will permit you to look at the construction manual which is a real help when troubleshooting).
Be informed and don't get swindled. Many savvy ops who simply lacked knowledge about the GLA-1000 have been suckered and have paid way, way too much. (I am looking in the mirror here).
For a project amp, I might pay up to $150 for a GLA-1000, but no more. As a ready-to-go regular operating adjunct, I wouldn't pay ten dollars for one.
My ownership of one lasted only a few weeks; a good friend pointed me to info about this amp, gave mine the once-over and advised me to cut my losses and unload it. I did so, with full disclosure of the great potential and existing deficiencies of this model, letting it go for a very low price.
I don't hate this amp; I do regret that a model with this many issues was rather aggressively marketed in its day and that so many of them are offered on e-Bay and at hamfest swapmeets at quite unjustifiable prices. But, as I also said above, if you are interested in an excellent platform for a project that will result in a very neat amp, this may be the one for you. For the money spent on the amp and the parts for conversion, new tubes, etc., and time spent fabricating metal pieces and so on, you will be doing this as a labor of love and not as a sound means of giving your HF station the occasionally-needed extra oomph at a reasonable price.
If you can get one really, really cheap, then go for it if you wish to educate yourself on amplifier design and have the satisfaction of doing what we hams used to do all the time: improving our rigs and learning by doing.
- Kevin WA7VTD
Oregon City, OR
|
|
KA0CSL
|
Rating: 1/5
|
Oct 30, 2006 14:05
|
Send this review to a friend
|
|
Switches Suck!
|
Time owned: more than 12 months
|
|
This unit is a good cheap unit. watch out for the band switch and others they wear out and parts are impossiable to obtain.
|
|
WA2JJH
|
Rating: 2/5
|
Mar 6, 2004 20:51
|
Send this review to a friend
|
|
If you can get one for under $150, it is a good little amp.
|
Time owned: more than 12 months
|
Overpaid for mine on ebay. Paid about $350 with shipping.
Maybe it is comparing apples to oranges. However my Heathkit HL-2200(different case, same amp as the SB-220/1) out performs this amp.
Yes, the heathkit is a dual 3-500Z, but the original EIMACS in it are soft. So the output power when run on 110VAC is about the same.
Got this on ebay. The seller said he just put new tubes in it.
No matter what band, 100W pep in would produce only about 500-550W out.
The amp is hard to tune. On high SWR's the tuning cap arcs. The circuit breaker blows often.
The caps positions are critical.
Maybe the SB-220 is so much of a better amp.
By comparing the two, it was no contest.
This is the original GLA-1000, I find it to much of a pain in the butt to use. They relay is a real clinker(LOUD)
One the plus side. 10M MOD is a snap. The amp is real tiny compared to any other tube amp.
I remember DENTRONS QST ad for it. G.L.A.= GOOD LITTLE AMP.
If you can buy a SB-220/1 for $200 more.....PAY THE $200!
There is the GLA-1000 A and B. I think there was a C as well. Perhaps the later ones were better.
Since I have a real good amplifier(HL-2200), I would sell the GLA-1000 for $150 and not lose sleep! Seems that 500W out for a full 100W in, shows low efficiency.
DO GET SUCKERED ON EBAY< AND OVER PAY ON THIS AMP.
Its an amplifier, with nothing special to offer.
For only 500W out you are much better going solid state.
If it put out lets say 700W, did not arc, and trip a circuit breaker on SWR's just over 3:1, it would be a good little amp.
It could be that I got a lemon.
|
|
KO4NR
|
Rating: 4/5
|
Feb 26, 2002 10:45
|
Send this review to a friend
|
|
New Tube Conversion to GI6B or GI7B Tubes
|
Time owned: more than 12 months
|
There is a new conversion being done on these amps. Using the orginial transformer but with a voltage doubler, 12.6 filament transformer and winding a new coil for 10/20 and 15 meters is all that is required to use the GI7B or GI6B tube. These tubes are Russian Ceramic tubes and are very inexpensive right now. Still get 500 watts or so on 80, 40, and 20 meters with about 400 to 450 on 10, 15 and 17 (tuned in the 15 meter bandswitch position).
If you don't like sweep tubes but like the looks and small size of these little amps, Go For It!! I have pictures if you want to see them.
73,
Bill Smith KO4NR
|
|
KO4NR
|
Rating: 4/5
|
Nov 16, 2001 15:49
|
Send this review to a friend
|
|
New Tube Conversion Design
|
Time owned: more than 12 months
|
This new tube conversion design for the Svetlana EL-509/6KG6 tubes is a refinement of the orginial Svetlana conversion on their web site for the Dentron GLA-1000 series of amplifiers. I am in the middle of redoing one of my amps and will convey the results when I am finished. This design by PA0FRI solves the problem of trying to tune out the high input capacitance of the Svetlana tubes. Increase power out on 10 and 15 is assured with this design.
http://hem.passagen.se/sm0vpo/tx/500w-txt.htm
Orginial Svetlana article here:
http://www.svetlana.com/docs/TechBulletins/technoteNO.32.html
73,
Bill Smith KO4NR
|
|
KO4NR
|
Rating: 4/5
|
Aug 28, 2001 04:38
|
Send this review to a friend
|
|
Amps worth a second look!!
|
Time owned: more than 12 months
|
I have converted several of these little amps over to the Svetlana EL-509/6KG6 tubes as well as added several modifications and betterments. As an example FAR Circuits now offers in kind replacments for the orginial circuit boards, (RF Board, Power Supply Board, and a copy of the Tuned Input Board found in the GLA-1000B). The latter can be used to add a tuned input into the GLA-1000. In addition FAR Circuits offers RF circuit boards redesigned for the Svetlana EL-509/6KG6 tubes that will accomadate the orginial Svetlana EL-509 socket. They also have redesigned the Power Supply board to accomadate the use of Radial lead type electrolytic capacitors. So there you go two different ways to go with the circuit boards in your GLA-1000 series amplifier.
The Dentron GLA-1000 series of amplifiers are a very good value considering one in excellent condition can be had for anywhere from $100.00 to $300.00 depending on where you shop. I have had one given to me!! They were designed to keep costs down and the size small.
They are a small but powerful addition to any shack!! I also like the looks of the front panel.
As modified and using Svetlana El-509/6KG6 tubes I get about 550 to 600 watts PEP out on 80,40 and 20 meters with 60 to 65 watts of drive. On 15 and 10 meters I get out about 400 to 450 watts PEP out with the same amount of drive. Key down power readings will be lower because the plate voltage drops.
I have kept complete records of all the modifications and betterments and can email them to anyone interested at no charge.
73,
Bill Smith KO4NR
|
|
If you have any questions, problems, or suggestions about Reviews,
please email your Reviews Manager.
|
|
|
|
|
