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 | Transceivers: VHF/UHF+ Amateur Base/Mobile (non hand-held) | Standard Elektrik Lorenz (S.E.L.) SEM-35 Help


Reviews Summary for Standard Elektrik Lorenz (S.E.L.) SEM-35
Standard Elektrik Lorenz (S.E.L.)  SEM-35 Reviews: 5 Average rating: 4.6/5 MSRP: $Unknown
Description: Military Tactical Man-Pack radio, VHF FM
Product is not in production.
More info: http://
Email Subscription
You are not subscribed to this review.

Subscribe!
My Subscriptions
Subscriptions Help

You can write your own review of the Standard Elektrik Lorenz (S.E.L.) SEM-35.

KM4BA Rating: 5/5 Mar 2, 2007 14:44 Send this review to a friend
well made, very fun piece of cold-war kit!  Time owned: more than 12 months
The SEM-35 is a fun rig for someone wanting to play with green radios without competing with the re-enactors for expensive PRC-77's and PRC-25's.

They are very well made, a bit stronger mechanically than the US counterparts.

They will cover both 6 and 10m ham bands, and the way the bandswitch is aligned makes me think the designer might have been a ham, as common 6&10m fm calling frequencies require minimum knob twiddling.

Some feel the PRC-77 is better RF-wise, but realistically there is very little difference in capability between the two radios.

Accessories are the common "old family" H-33 & LS-166 type.

Another advantage is the battery packs take common D cell's and will happily run on alkalines for some time. You can also feed them directly with 24v and a simple wall wart or switcher supply.

Radios currently being surplused in Europe tend to be very well maintained, extremely clean, and are quite the bargain compared to US kit. I've not seen any US PRC's released in similar condition, usually the US radios are very rough unless they have been refurbished.

Even if you don't speak German, it's easy to figure the controls out.

We use several with scouts, and they would rather talk to each other on the SEM-35's in backpacks than use the latest generation ham HF gear!

More info on the SEM-35 can be found here:
< http://www.greenradios.com/Radios/German/Sem/Sem25-35/Sem_35.html >
 
PE1RLN Rating: 5/5 Jun 5, 2006 06:11 Send this review to a friend
in addition: great for QRP!  Time owned: 3 to 6 months
I have to add some comment to my previous review.

Yesterday I worked +1000km at 29.650MHz FM with only the SEM-35's output. I didn't use another antenna or so, just the supplied 2.5m whip.

So, if you are planning to go QRP, consider this one!
 
W7SVJ Rating: 3/5 May 9, 2006 08:03 Send this review to a friend
Summary-as designed  Time owned: more than 12 months
My opinion differs slightly form the previous two posts, as follows:

1. From a construction quality point of view, it is exemplary, very nice workmanship, quality casting and finishing, etc.

2. From and engineering perspective, I believe it is overly complex, and field repairs beyond module replacement would be difficult, due to sub-modules being soldered in place.(This may have been the intent, depending upon how many levels of maintenance were present in the German Military) The power consumption seem excessive for a one watt radio, and although a switching converter is used, it is relatively inefficient and uses resistive dividers profusely, rather than switching regulation. The transmitter is AGC'ed to the receiver synthesizer, which limits the transmit frequency stability to that of the stability of the 11.5 MHz discriminator, which is admittedly not all that bad, although it moves somewhat over temperature. It is quite heavy for the vintage, although quite rugged. The use of standard D-cell power is nice for the civilian user, but rather clumsy for a tactical radio, as a battery change takes several minutes, unless one has extra cell holders. A custom pack would undoubtedly have higher power density, and may well have been available at some point.

In conclusion, I feel that the SEM-35 is a very well made radio, but given that it is at least five years junior to the PRC-77, It would seem that steps could havve been taken to modernize it somewhat. It seems to have been built upon the prevailing technolgy of the SCR-300 and PRC-8/9/10 (transmit discriminator locking)and the PRC-25/77 (solid state, frequency synthesis), but one can only wonder why Lorenz felt it necessary to use the large mechanical tuner, and not spend a bit more effort to reduce weght and power consumption. In the final analysis, however, it is still one of my favorites!
 
PE1RLN Rating: 5/5 Apr 17, 2006 05:19 Send this review to a friend
Rugged and reliable  Time owned: 0 to 3 months
The SEM-35 is larger than you would like, it gives only 1 Watt of FM power. You could buy a Yaesu transceiver which covers 10m, 6m, 2m and 70cm with up to 35 Watts of power in a much smaller package. Add the options in such a newer rig and you'll see it is a better choice.

Or...

Drop it, leave it in the rain, use it on a battery for a few hours, let it unattended by some children. I bet you'll not recognise it anymore when you come back.

The SEM-35 is very good for what it is made for: short distance communication in rough conditions, something the Japanese radios just aren't made for.
The power is sufficient to cover a rather great area and the 1W (appears to reach 2W) is the same as you get from a commercial HT. The antenna I use is the foldable 2.5 m long whip which I already bought once and that isn't a whip you would want to mount on a regular HT.
The results are amazing: clear audio and it is possible to use it on commercial HAM rigs by lowering the bandwidth internally.

Some mayor positive sides (also mentioned elsewhere probably):

- squelch works very nice and is adjustable inside
- bandwidht is adjustable to be used on commercial rigs
- external antenna can be used on regular BNC connector, even the SEL base antenna which has a very nice autotuner inside for only a few bucks!
- it works on regular batteries and even on 13,8V (although it seems that the voltage may be a bit higher, but it works alright)
- it is very rugged, whatertight and fool-proof

Altogether, you shouldn't use this rig if you have other plans with it than what it is meant for. It covers 2 HAM bands, even CB, and is only for rather short distance.
 
AC5XP Rating: 5/5 Feb 5, 2002 19:01 Send this review to a friend
One tough little radio  Time owned: more than 12 months
SEM-35 Military Man-Pack radio

The SEM-35 is a German military radio, primarily developed for man-portable use in the field. It also can be used in a vehicular mounted configuration, a mounting bracket is available for this purpose.
It is a VHF radio which covers the range 26,00 - 69,95 MHz in 50 kHz steps. Power output is 1W or 150 mW, user-selectable from the front panel.
It was developed in the late fifties/early sixties by Standard Elektrik Lorenz (S.E.L.) in West Germany. This was one of the first military radios that the Germans were allowed to develop themselves again after the war, before that most of the German produced military radios were of US design (examples of these were GRC-9 by Telefunken, and the RT-66/67/68 by SEL)
The radio is designed well, both mechanical and electrical. The construction is of plug-in, modular design with only PFTE insulated wiring. Every coaxial connection terminates into gold-plated SMA-style connectors, no compromises here.
The glass-epoxy boards inside the modules are individually shielded and coated with a varnish to prevent corrosion. Everything is placed logically and easy to reach in case service would be needed. It is a pleasure to look at its insides in all aspects, a true work of art with only the best components and construction techniques used. And that great inside smell, I wish that was sold as a fragrance!
This radio is sometimes called the German PRC-77, as both radios were designed for the same purpose, and cover almost identical frequency.
However, in a direct comparison the SEM-35 wins in almost every aspect. To name a few:

- SEM-35 runs of standard mono-cells (12 are needed). A n electronic power conditioner makes sure the radio gets its voltage, even when the batteries are almost empty. In fact, the built-in power conditioner keeps the radio running anywhere from 8V to 32V as I tested once. The conditioner is extremely efficient, it draws about 50 mA from the batteries during receive. The PRC-77 on the other hand needs a difficult to get custom battery, and doesn't tolerate voltage drop much at the end of the battery's life

- The SEM-35 covers the 10-meter band as well, a plus for ham users. PRC-77 starts from 30 MHz and up.

- The SEM-35 is of much better construction than the PRC-77 for both insides and outside. The PRC-77's stamped-aluminum case is much less rigid than the diecast aluminum SEM35 case.

- SEM-35 FM modulation is better and slightly narrower than the PRC

- Power output is slightly better for the PRC-77 (I think that radio is 2 watts where the SEM-35 is specified for 1 watt)

- PRC-77 is somewhat lighter (the thicker Al-case for the SEM means more weight for the user)

Two mechanical dials are used to select the radio's frequency, one for the MHz steps, and the other for the 50 kHz steps. The radio's frequency coverage is split in two bands, selectable with a band-switch on the front of the radio. Modulation is FM, and not too wide for its age.
What is nice about this radio is that it covers the 10 meter band, as well as the 6 meter band meaning it is ideal for VHF Ham use. The two bands are split such that when one is tuned at 29 MHz in the low band, and one switches to the high band, one is very close to the 50 MHz already, meaning one does not have to crank to many mechanical channels to get there. Nice from the manufacturer to keep us hams in mind! (just kidding of course, it is obviously dumb luck)
The receiver is very sensitive for such a wide bandwidth (compared to modern ham radios). It turns out to be a cinch to use this radio with a Japanese radio as the opposite station, there are no problems with the modulation (or receiver) bandwidth being too wide for the SEM-35.
What also impressed me is the sharp cutoff for the receiver passband once one is slightly outside it. The radio probably uses a crystal filter but I am not sure about this as I have no circuit diagram. Also, the radio seems to be quite robust against out-of-band signals, I was able to operate my ham transceiver at 100 watts at 10 meter without the SEM suffering from it on 6 meter. Quite an accomplishment for a radio design that is more than 40 years old.
Another impressive feat was the fact that the radio is within 50 Hz of the selected frequency across the bands. This is astonishing given the fact that the rig's channel separation is 50 kHz! Frequency synthesis seems to be accomplished by mixing crystals against a low-frequency VFO but I can only guess here judging the insides, as said I have no diagram for it.
The radio has a very nice working noise-squelch, which drives a bipolar relay. It does not have the 250 Hz tone-squelch, which is standard on US equipment for this band.
Two antennas can be used, a long whip and a short whip. The two different whips have threaded rods of different length on their mounting base, which press against a switch on the inside of the radio, assuring proper matching for the different antenna types. The radio also can be used into 50 ohms, a BNC connector is present on the front for this purpose. But no whip antenna should be mounted when using this 50-ohm output.
As a handset, the older H-33 style carbon-mike based handset can be used.
Operating this radio is a lot of fun, and it is amazing how well it works from only 1 watt (although my radio gives off almost two watts, it did this stock).
The simple power supply requirements for this radio help to keep things comfortable, which is either from internal mono-cells or from external sources anywhere between 10V and 32V DC.
The radios go in good condition for about $300, probably because they are difficult to get in nice condition. Most of what one finds from the several sources is heavily used, which also lowers the price. But because of its ruggedness, it still will work without a problem. And from the inside, they all look like new I have found, so don't let the missing outside paint fool you.
See you with your SEM-35 at the next field-day!
 


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